
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		//		new Main().solveA();
		//		new Main().solveB();
		new Main().solveC();
		// new Main().solveD();
	}

	private void solveA() {
		Scanner scanner = null;
		int numX = 0;
		int numA = 0;
		int numB = 0;

		try {
			scanner = new Scanner(System.in);
			numX = scanner.nextInt();
			numA = scanner.nextInt();
			numB = scanner.nextInt();

			System.out.println((numX - numA) % numB);

			System.out.println("");

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	}

	private void solveB() {
		Scanner scanner = null;
		int numA = 0;
		int numB = 0;
		int numC = 0;
		int numX = 0;

		try {
			scanner = new Scanner(System.in);
			numA = scanner.nextInt();
			numB = scanner.nextInt();
			numC = scanner.nextInt();
			numX = scanner.nextInt();

			int res = 0;
			for (int i = 0; i <= numA; i++) {
				for (int j = 0; j <= numB; j++) {
					for (int k = 0; k <= numC; k++) {
						if (i * 500 + j * 100 + k * 50 == numX) {
							res++;
						}
					}
				}
			}

			System.out.println(res);

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	}

	private int getAme(int[][] wk, int x, int y) {
		int res = 0;

		if (x >= 2 || y >= wk[0].length) {
			return 0;
		}

		int val1 = getAme(wk, x + 1, y) + wk[x][y];
		int val2 = getAme(wk, x, y + 1) + wk[x][y];

		res = Math.max(val1, val2);
		return res;
	}

	private void solveC() {
		Scanner scanner = null;
		int numN = 0;

		try {
			scanner = new Scanner(System.in);
			numN = scanner.nextInt();

			int[][] wk = new int[2][numN];

			for (int i = 0; i < wk.length; i++) {
				for (int j = 0; j < numN; j++) {
					wk[i][j] = scanner.nextInt();
				}
			}

			System.out.println(getAme(wk, 0, 0));

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	}

	private void solveD() {
		Scanner scanner = null;
		int numN = 0;
		int numK = 0;
		int numS = 0;

		try {
			scanner = new Scanner(System.in);
			numN = scanner.nextInt();

			System.out.println("");

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	}
} import java.util.Scanner; Scanner java.util public class Main {

	public static void main(String[] args) {
		//		new Main().solveA();
		//		new Main().solveB();
		new Main().solveC();
		// new Main().solveD();
	}

	private void solveA() {
		Scanner scanner = null;
		int numX = 0;
		int numA = 0;
		int numB = 0;

		try {
			scanner = new Scanner(System.in);
			numX = scanner.nextInt();
			numA = scanner.nextInt();
			numB = scanner.nextInt();

			System.out.println((numX - numA) % numB);

			System.out.println("");

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	}

	private void solveB() {
		Scanner scanner = null;
		int numA = 0;
		int numB = 0;
		int numC = 0;
		int numX = 0;

		try {
			scanner = new Scanner(System.in);
			numA = scanner.nextInt();
			numB = scanner.nextInt();
			numC = scanner.nextInt();
			numX = scanner.nextInt();

			int res = 0;
			for (int i = 0; i <= numA; i++) {
				for (int j = 0; j <= numB; j++) {
					for (int k = 0; k <= numC; k++) {
						if (i * 500 + j * 100 + k * 50 == numX) {
							res++;
						}
					}
				}
			}

			System.out.println(res);

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	}

	private int getAme(int[][] wk, int x, int y) {
		int res = 0;

		if (x >= 2 || y >= wk[0].length) {
			return 0;
		}

		int val1 = getAme(wk, x + 1, y) + wk[x][y];
		int val2 = getAme(wk, x, y + 1) + wk[x][y];

		res = Math.max(val1, val2);
		return res;
	}

	private void solveC() {
		Scanner scanner = null;
		int numN = 0;

		try {
			scanner = new Scanner(System.in);
			numN = scanner.nextInt();

			int[][] wk = new int[2][numN];

			for (int i = 0; i < wk.length; i++) {
				for (int j = 0; j < numN; j++) {
					wk[i][j] = scanner.nextInt();
				}
			}

			System.out.println(getAme(wk, 0, 0));

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	}

	private void solveD() {
		Scanner scanner = null;
		int numN = 0;
		int numK = 0;
		int numS = 0;

		try {
			scanner = new Scanner(System.in);
			numN = scanner.nextInt();

			System.out.println("");

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	}
} Main public static void main(String[] args) {
		//		new Main().solveA();
		//		new Main().solveB();
		new Main().solveC();
		// new Main().solveD();
	} main {
		//		new Main().solveA();
		//		new Main().solveB();
		new Main().solveC();
		// new Main().solveD();
	} new Main().solveC() new Main().solveC new Main() String[] args args private void solveA() {
		Scanner scanner = null;
		int numX = 0;
		int numA = 0;
		int numB = 0;

		try {
			scanner = new Scanner(System.in);
			numX = scanner.nextInt();
			numA = scanner.nextInt();
			numB = scanner.nextInt();

			System.out.println((numX - numA) % numB);

			System.out.println("");

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	} solveA {
		Scanner scanner = null;
		int numX = 0;
		int numA = 0;
		int numB = 0;

		try {
			scanner = new Scanner(System.in);
			numX = scanner.nextInt();
			numA = scanner.nextInt();
			numB = scanner.nextInt();

			System.out.println((numX - numA) % numB);

			System.out.println("");

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	} Scanner scanner = null; scanner null int numX = 0; numX 0 int numA = 0; numA 0 int numB = 0; numB 0 try {
			scanner = new Scanner(System.in);
			numX = scanner.nextInt();
			numA = scanner.nextInt();
			numB = scanner.nextInt();

			System.out.println((numX - numA) % numB);

			System.out.println("");

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		} {
			if (scanner != null) {
				scanner.close();
			}
		} if (scanner != null) {
				scanner.close();
			} scanner != null scanner null {
				scanner.close();
			} scanner.close() scanner.close scanner {
			scanner = new Scanner(System.in);
			numX = scanner.nextInt();
			numA = scanner.nextInt();
			numB = scanner.nextInt();

			System.out.println((numX - numA) % numB);

			System.out.println("");

		} scanner = new Scanner(System.in) scanner new Scanner(System.in) numX = scanner.nextInt() numX scanner.nextInt() scanner.nextInt scanner numA = scanner.nextInt() numA scanner.nextInt() scanner.nextInt scanner numB = scanner.nextInt() numB scanner.nextInt() scanner.nextInt scanner System.out.println((numX - numA) % numB) System.out.println System.out System System.out (numX - numA) % numB (numX - numA) numX numA numB System.out.println("") System.out.println System.out System System.out "" private void solveB() {
		Scanner scanner = null;
		int numA = 0;
		int numB = 0;
		int numC = 0;
		int numX = 0;

		try {
			scanner = new Scanner(System.in);
			numA = scanner.nextInt();
			numB = scanner.nextInt();
			numC = scanner.nextInt();
			numX = scanner.nextInt();

			int res = 0;
			for (int i = 0; i <= numA; i++) {
				for (int j = 0; j <= numB; j++) {
					for (int k = 0; k <= numC; k++) {
						if (i * 500 + j * 100 + k * 50 == numX) {
							res++;
						}
					}
				}
			}

			System.out.println(res);

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	} solveB {
		Scanner scanner = null;
		int numA = 0;
		int numB = 0;
		int numC = 0;
		int numX = 0;

		try {
			scanner = new Scanner(System.in);
			numA = scanner.nextInt();
			numB = scanner.nextInt();
			numC = scanner.nextInt();
			numX = scanner.nextInt();

			int res = 0;
			for (int i = 0; i <= numA; i++) {
				for (int j = 0; j <= numB; j++) {
					for (int k = 0; k <= numC; k++) {
						if (i * 500 + j * 100 + k * 50 == numX) {
							res++;
						}
					}
				}
			}

			System.out.println(res);

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	} Scanner scanner = null; scanner null int numA = 0; numA 0 int numB = 0; numB 0 int numC = 0; numC 0 int numX = 0; numX 0 try {
			scanner = new Scanner(System.in);
			numA = scanner.nextInt();
			numB = scanner.nextInt();
			numC = scanner.nextInt();
			numX = scanner.nextInt();

			int res = 0;
			for (int i = 0; i <= numA; i++) {
				for (int j = 0; j <= numB; j++) {
					for (int k = 0; k <= numC; k++) {
						if (i * 500 + j * 100 + k * 50 == numX) {
							res++;
						}
					}
				}
			}

			System.out.println(res);

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		} {
			if (scanner != null) {
				scanner.close();
			}
		} if (scanner != null) {
				scanner.close();
			} scanner != null scanner null {
				scanner.close();
			} scanner.close() scanner.close scanner {
			scanner = new Scanner(System.in);
			numA = scanner.nextInt();
			numB = scanner.nextInt();
			numC = scanner.nextInt();
			numX = scanner.nextInt();

			int res = 0;
			for (int i = 0; i <= numA; i++) {
				for (int j = 0; j <= numB; j++) {
					for (int k = 0; k <= numC; k++) {
						if (i * 500 + j * 100 + k * 50 == numX) {
							res++;
						}
					}
				}
			}

			System.out.println(res);

		} scanner = new Scanner(System.in) scanner new Scanner(System.in) numA = scanner.nextInt() numA scanner.nextInt() scanner.nextInt scanner numB = scanner.nextInt() numB scanner.nextInt() scanner.nextInt scanner numC = scanner.nextInt() numC scanner.nextInt() scanner.nextInt scanner numX = scanner.nextInt() numX scanner.nextInt() scanner.nextInt scanner int res = 0; res 0 for (int i = 0; i <= numA; i++) {
				for (int j = 0; j <= numB; j++) {
					for (int k = 0; k <= numC; k++) {
						if (i * 500 + j * 100 + k * 50 == numX) {
							res++;
						}
					}
				}
			} int i = 0; int i = 0; i 0 i <= numA i numA i++ i++ i {
				for (int j = 0; j <= numB; j++) {
					for (int k = 0; k <= numC; k++) {
						if (i * 500 + j * 100 + k * 50 == numX) {
							res++;
						}
					}
				}
			} {
				for (int j = 0; j <= numB; j++) {
					for (int k = 0; k <= numC; k++) {
						if (i * 500 + j * 100 + k * 50 == numX) {
							res++;
						}
					}
				}
			} for (int j = 0; j <= numB; j++) {
					for (int k = 0; k <= numC; k++) {
						if (i * 500 + j * 100 + k * 50 == numX) {
							res++;
						}
					}
				} int j = 0; int j = 0; j 0 j <= numB j numB j++ j++ j {
					for (int k = 0; k <= numC; k++) {
						if (i * 500 + j * 100 + k * 50 == numX) {
							res++;
						}
					}
				} {
					for (int k = 0; k <= numC; k++) {
						if (i * 500 + j * 100 + k * 50 == numX) {
							res++;
						}
					}
				} for (int k = 0; k <= numC; k++) {
						if (i * 500 + j * 100 + k * 50 == numX) {
							res++;
						}
					} int k = 0; int k = 0; k 0 k <= numC k numC k++ k++ k {
						if (i * 500 + j * 100 + k * 50 == numX) {
							res++;
						}
					} {
						if (i * 500 + j * 100 + k * 50 == numX) {
							res++;
						}
					} if (i * 500 + j * 100 + k * 50 == numX) {
							res++;
						} i * 500 + j * 100 + k * 50 == numX i * 500 + j * 100 + k * 50 i * 500 + j * 100 + k * 50 i * 500 i 500 j * 100 j 100 k * 50 k 50 numX {
							res++;
						} res++ res System.out.println(res) System.out.println System.out System System.out res private int getAme(int[][] wk, int x, int y) {
		int res = 0;

		if (x >= 2 || y >= wk[0].length) {
			return 0;
		}

		int val1 = getAme(wk, x + 1, y) + wk[x][y];
		int val2 = getAme(wk, x, y + 1) + wk[x][y];

		res = Math.max(val1, val2);
		return res;
	} getAme {
		int res = 0;

		if (x >= 2 || y >= wk[0].length) {
			return 0;
		}

		int val1 = getAme(wk, x + 1, y) + wk[x][y];
		int val2 = getAme(wk, x, y + 1) + wk[x][y];

		res = Math.max(val1, val2);
		return res;
	} int res = 0; res 0 if (x >= 2 || y >= wk[0].length) {
			return 0;
		} x >= 2 || y >= wk[0].length x >= 2 x 2 y >= wk[0].length y wk[0].length wk[0] wk 0 wk[0].length {
			return 0;
		} return 0; 0 int val1 = getAme(wk, x + 1, y) + wk[x][y]; val1 getAme(wk, x + 1, y) + wk[x][y] getAme(wk, x + 1, y) getAme wk x + 1 x 1 y wk[x][y] wk[x] wk x y int val2 = getAme(wk, x, y + 1) + wk[x][y]; val2 getAme(wk, x, y + 1) + wk[x][y] getAme(wk, x, y + 1) getAme wk x y + 1 y 1 wk[x][y] wk[x] wk x y res = Math.max(val1, val2) res Math.max(val1, val2) Math.max Math val1 val2 return res; res int[][] wk wk int x x int y y private void solveC() {
		Scanner scanner = null;
		int numN = 0;

		try {
			scanner = new Scanner(System.in);
			numN = scanner.nextInt();

			int[][] wk = new int[2][numN];

			for (int i = 0; i < wk.length; i++) {
				for (int j = 0; j < numN; j++) {
					wk[i][j] = scanner.nextInt();
				}
			}

			System.out.println(getAme(wk, 0, 0));

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	} solveC {
		Scanner scanner = null;
		int numN = 0;

		try {
			scanner = new Scanner(System.in);
			numN = scanner.nextInt();

			int[][] wk = new int[2][numN];

			for (int i = 0; i < wk.length; i++) {
				for (int j = 0; j < numN; j++) {
					wk[i][j] = scanner.nextInt();
				}
			}

			System.out.println(getAme(wk, 0, 0));

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	} Scanner scanner = null; scanner null int numN = 0; numN 0 try {
			scanner = new Scanner(System.in);
			numN = scanner.nextInt();

			int[][] wk = new int[2][numN];

			for (int i = 0; i < wk.length; i++) {
				for (int j = 0; j < numN; j++) {
					wk[i][j] = scanner.nextInt();
				}
			}

			System.out.println(getAme(wk, 0, 0));

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		} {
			if (scanner != null) {
				scanner.close();
			}
		} if (scanner != null) {
				scanner.close();
			} scanner != null scanner null {
				scanner.close();
			} scanner.close() scanner.close scanner {
			scanner = new Scanner(System.in);
			numN = scanner.nextInt();

			int[][] wk = new int[2][numN];

			for (int i = 0; i < wk.length; i++) {
				for (int j = 0; j < numN; j++) {
					wk[i][j] = scanner.nextInt();
				}
			}

			System.out.println(getAme(wk, 0, 0));

		} scanner = new Scanner(System.in) scanner new Scanner(System.in) numN = scanner.nextInt() numN scanner.nextInt() scanner.nextInt scanner int[][] wk = new int[2][numN]; wk new int[2][numN] 2 numN for (int i = 0; i < wk.length; i++) {
				for (int j = 0; j < numN; j++) {
					wk[i][j] = scanner.nextInt();
				}
			} int i = 0; int i = 0; i 0 i < wk.length i wk.length wk wk.length i++ i++ i {
				for (int j = 0; j < numN; j++) {
					wk[i][j] = scanner.nextInt();
				}
			} {
				for (int j = 0; j < numN; j++) {
					wk[i][j] = scanner.nextInt();
				}
			} for (int j = 0; j < numN; j++) {
					wk[i][j] = scanner.nextInt();
				} int j = 0; int j = 0; j 0 j < numN j numN j++ j++ j {
					wk[i][j] = scanner.nextInt();
				} {
					wk[i][j] = scanner.nextInt();
				} wk[i][j] = scanner.nextInt() wk[i][j] wk[i] wk i j scanner.nextInt() scanner.nextInt scanner System.out.println(getAme(wk, 0, 0)) System.out.println System.out System System.out getAme(wk, 0, 0) getAme wk 0 0 private void solveD() {
		Scanner scanner = null;
		int numN = 0;
		int numK = 0;
		int numS = 0;

		try {
			scanner = new Scanner(System.in);
			numN = scanner.nextInt();

			System.out.println("");

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	} solveD {
		Scanner scanner = null;
		int numN = 0;
		int numK = 0;
		int numS = 0;

		try {
			scanner = new Scanner(System.in);
			numN = scanner.nextInt();

			System.out.println("");

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	} Scanner scanner = null; scanner null int numN = 0; numN 0 int numK = 0; numK 0 int numS = 0; numS 0 try {
			scanner = new Scanner(System.in);
			numN = scanner.nextInt();

			System.out.println("");

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		} {
			if (scanner != null) {
				scanner.close();
			}
		} if (scanner != null) {
				scanner.close();
			} scanner != null scanner null {
				scanner.close();
			} scanner.close() scanner.close scanner {
			scanner = new Scanner(System.in);
			numN = scanner.nextInt();

			System.out.println("");

		} scanner = new Scanner(System.in) scanner new Scanner(System.in) numN = scanner.nextInt() numN scanner.nextInt() scanner.nextInt scanner System.out.println("") System.out.println System.out System System.out "" public class Main {

	public static void main(String[] args) {
		//		new Main().solveA();
		//		new Main().solveB();
		new Main().solveC();
		// new Main().solveD();
	}

	private void solveA() {
		Scanner scanner = null;
		int numX = 0;
		int numA = 0;
		int numB = 0;

		try {
			scanner = new Scanner(System.in);
			numX = scanner.nextInt();
			numA = scanner.nextInt();
			numB = scanner.nextInt();

			System.out.println((numX - numA) % numB);

			System.out.println("");

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	}

	private void solveB() {
		Scanner scanner = null;
		int numA = 0;
		int numB = 0;
		int numC = 0;
		int numX = 0;

		try {
			scanner = new Scanner(System.in);
			numA = scanner.nextInt();
			numB = scanner.nextInt();
			numC = scanner.nextInt();
			numX = scanner.nextInt();

			int res = 0;
			for (int i = 0; i <= numA; i++) {
				for (int j = 0; j <= numB; j++) {
					for (int k = 0; k <= numC; k++) {
						if (i * 500 + j * 100 + k * 50 == numX) {
							res++;
						}
					}
				}
			}

			System.out.println(res);

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	}

	private int getAme(int[][] wk, int x, int y) {
		int res = 0;

		if (x >= 2 || y >= wk[0].length) {
			return 0;
		}

		int val1 = getAme(wk, x + 1, y) + wk[x][y];
		int val2 = getAme(wk, x, y + 1) + wk[x][y];

		res = Math.max(val1, val2);
		return res;
	}

	private void solveC() {
		Scanner scanner = null;
		int numN = 0;

		try {
			scanner = new Scanner(System.in);
			numN = scanner.nextInt();

			int[][] wk = new int[2][numN];

			for (int i = 0; i < wk.length; i++) {
				for (int j = 0; j < numN; j++) {
					wk[i][j] = scanner.nextInt();
				}
			}

			System.out.println(getAme(wk, 0, 0));

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	}

	private void solveD() {
		Scanner scanner = null;
		int numN = 0;
		int numK = 0;
		int numS = 0;

		try {
			scanner = new Scanner(System.in);
			numN = scanner.nextInt();

			System.out.println("");

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	}
} public class Main {

	public static void main(String[] args) {
		//		new Main().solveA();
		//		new Main().solveB();
		new Main().solveC();
		// new Main().solveD();
	}

	private void solveA() {
		Scanner scanner = null;
		int numX = 0;
		int numA = 0;
		int numB = 0;

		try {
			scanner = new Scanner(System.in);
			numX = scanner.nextInt();
			numA = scanner.nextInt();
			numB = scanner.nextInt();

			System.out.println((numX - numA) % numB);

			System.out.println("");

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	}

	private void solveB() {
		Scanner scanner = null;
		int numA = 0;
		int numB = 0;
		int numC = 0;
		int numX = 0;

		try {
			scanner = new Scanner(System.in);
			numA = scanner.nextInt();
			numB = scanner.nextInt();
			numC = scanner.nextInt();
			numX = scanner.nextInt();

			int res = 0;
			for (int i = 0; i <= numA; i++) {
				for (int j = 0; j <= numB; j++) {
					for (int k = 0; k <= numC; k++) {
						if (i * 500 + j * 100 + k * 50 == numX) {
							res++;
						}
					}
				}
			}

			System.out.println(res);

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	}

	private int getAme(int[][] wk, int x, int y) {
		int res = 0;

		if (x >= 2 || y >= wk[0].length) {
			return 0;
		}

		int val1 = getAme(wk, x + 1, y) + wk[x][y];
		int val2 = getAme(wk, x, y + 1) + wk[x][y];

		res = Math.max(val1, val2);
		return res;
	}

	private void solveC() {
		Scanner scanner = null;
		int numN = 0;

		try {
			scanner = new Scanner(System.in);
			numN = scanner.nextInt();

			int[][] wk = new int[2][numN];

			for (int i = 0; i < wk.length; i++) {
				for (int j = 0; j < numN; j++) {
					wk[i][j] = scanner.nextInt();
				}
			}

			System.out.println(getAme(wk, 0, 0));

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	}

	private void solveD() {
		Scanner scanner = null;
		int numN = 0;
		int numK = 0;
		int numS = 0;

		try {
			scanner = new Scanner(System.in);
			numN = scanner.nextInt();

			System.out.println("");

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	}
} Main

import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		//		new Main().solveA();
		//		new Main().solveB();
		new Main().solveC();
		// new Main().solveD();
	}

	private void solveA() {
		Scanner scanner = null;
		int numX = 0;
		int numA = 0;
		int numB = 0;

		try {
			scanner = new Scanner(System.in);
			numX = scanner.nextInt();
			numA = scanner.nextInt();
			numB = scanner.nextInt();

			System.out.println((numX - numA) % numB);

			System.out.println("");

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	}

	private void solveB() {
		Scanner scanner = null;
		int numA = 0;
		int numB = 0;
		int numC = 0;
		int numX = 0;

		try {
			scanner = new Scanner(System.in);
			numA = scanner.nextInt();
			numB = scanner.nextInt();
			numC = scanner.nextInt();
			numX = scanner.nextInt();

			int res = 0;
			for (int i = 0; i <= numA; i++) {
				for (int j = 0; j <= numB; j++) {
					for (int k = 0; k <= numC; k++) {
						if (i * 500 + j * 100 + k * 50 == numX) {
							res++;
						}
					}
				}
			}

			System.out.println(res);

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	}

	private int getAme(int[][] wk, int x, int y) {
		int res = 0;

		if (x >= 2 || y >= wk[0].length) {
			return 0;
		}

		int val1 = getAme(wk, x + 1, y) + wk[x][y];
		int val2 = getAme(wk, x, y + 1) + wk[x][y];

		res = Math.max(val1, val2);
		return res;
	}

	private void solveC() {
		Scanner scanner = null;
		int numN = 0;

		try {
			scanner = new Scanner(System.in);
			numN = scanner.nextInt();

			int[][] wk = new int[2][numN];

			for (int i = 0; i < wk.length; i++) {
				for (int j = 0; j < numN; j++) {
					wk[i][j] = scanner.nextInt();
				}
			}

			System.out.println(getAme(wk, 0, 0));

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	}

	private void solveD() {
		Scanner scanner = null;
		int numN = 0;
		int numK = 0;
		int numS = 0;

		try {
			scanner = new Scanner(System.in);
			numN = scanner.nextInt();

			System.out.println("");

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	}
}