import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		// TODO 自動生成されたメソッド・スタブ
		Scanner scanner = new Scanner(System.in);
		int x1 = scanner.nextInt();
		int x2 = scanner.nextInt();
		int x3 = scanner.nextInt();
		int x4 = scanner.nextInt();
		int x5 = scanner.nextInt();
		int answer = 0;

		int [] array = new int[]{x1, x2, x3, x4, x5};
		for (int i =0; i < 5; i++) {
			boolean bool = array[i] == 0;
			if (bool == true) {
				if(i == 4) {
					answer = array[i - 1] + 1;
					break;
				} else {
					answer = array[i + 1] - 1;
					break;
				}
			}
		}

		System.out.println(answer);

	}

} import java.util.Scanner; Scanner java.util public class Main {

	public static void main(String[] args) {
		// TODO 自動生成されたメソッド・スタブ
		Scanner scanner = new Scanner(System.in);
		int x1 = scanner.nextInt();
		int x2 = scanner.nextInt();
		int x3 = scanner.nextInt();
		int x4 = scanner.nextInt();
		int x5 = scanner.nextInt();
		int answer = 0;

		int [] array = new int[]{x1, x2, x3, x4, x5};
		for (int i =0; i < 5; i++) {
			boolean bool = array[i] == 0;
			if (bool == true) {
				if(i == 4) {
					answer = array[i - 1] + 1;
					break;
				} else {
					answer = array[i + 1] - 1;
					break;
				}
			}
		}

		System.out.println(answer);

	}

} Main public static void main(String[] args) {
		// TODO 自動生成されたメソッド・スタブ
		Scanner scanner = new Scanner(System.in);
		int x1 = scanner.nextInt();
		int x2 = scanner.nextInt();
		int x3 = scanner.nextInt();
		int x4 = scanner.nextInt();
		int x5 = scanner.nextInt();
		int answer = 0;

		int [] array = new int[]{x1, x2, x3, x4, x5};
		for (int i =0; i < 5; i++) {
			boolean bool = array[i] == 0;
			if (bool == true) {
				if(i == 4) {
					answer = array[i - 1] + 1;
					break;
				} else {
					answer = array[i + 1] - 1;
					break;
				}
			}
		}

		System.out.println(answer);

	} main {
		// TODO 自動生成されたメソッド・スタブ
		Scanner scanner = new Scanner(System.in);
		int x1 = scanner.nextInt();
		int x2 = scanner.nextInt();
		int x3 = scanner.nextInt();
		int x4 = scanner.nextInt();
		int x5 = scanner.nextInt();
		int answer = 0;

		int [] array = new int[]{x1, x2, x3, x4, x5};
		for (int i =0; i < 5; i++) {
			boolean bool = array[i] == 0;
			if (bool == true) {
				if(i == 4) {
					answer = array[i - 1] + 1;
					break;
				} else {
					answer = array[i + 1] - 1;
					break;
				}
			}
		}

		System.out.println(answer);

	} Scanner scanner = new Scanner(System.in); scanner new Scanner(System.in) int x1 = scanner.nextInt(); x1 scanner.nextInt() scanner.nextInt scanner int x2 = scanner.nextInt(); x2 scanner.nextInt() scanner.nextInt scanner int x3 = scanner.nextInt(); x3 scanner.nextInt() scanner.nextInt scanner int x4 = scanner.nextInt(); x4 scanner.nextInt() scanner.nextInt scanner int x5 = scanner.nextInt(); x5 scanner.nextInt() scanner.nextInt scanner int answer = 0; answer 0 int [] array = new int[]{x1, x2, x3, x4, x5}; array new int[]{x1, x2, x3, x4, x5} for (int i =0; i < 5; i++) {
			boolean bool = array[i] == 0;
			if (bool == true) {
				if(i == 4) {
					answer = array[i - 1] + 1;
					break;
				} else {
					answer = array[i + 1] - 1;
					break;
				}
			}
		} int i =0; int i =0; i 0 i < 5 i 5 i++ i++ i {
			boolean bool = array[i] == 0;
			if (bool == true) {
				if(i == 4) {
					answer = array[i - 1] + 1;
					break;
				} else {
					answer = array[i + 1] - 1;
					break;
				}
			}
		} {
			boolean bool = array[i] == 0;
			if (bool == true) {
				if(i == 4) {
					answer = array[i - 1] + 1;
					break;
				} else {
					answer = array[i + 1] - 1;
					break;
				}
			}
		} boolean bool = array[i] == 0; bool array[i] == 0 array[i] array i 0 if (bool == true) {
				if(i == 4) {
					answer = array[i - 1] + 1;
					break;
				} else {
					answer = array[i + 1] - 1;
					break;
				}
			} bool == true bool true {
				if(i == 4) {
					answer = array[i - 1] + 1;
					break;
				} else {
					answer = array[i + 1] - 1;
					break;
				}
			} if(i == 4) {
					answer = array[i - 1] + 1;
					break;
				} else {
					answer = array[i + 1] - 1;
					break;
				} i == 4 i 4 {
					answer = array[i - 1] + 1;
					break;
				} answer = array[i - 1] + 1 answer array[i - 1] + 1 array[i - 1] array i - 1 i 1 1 break; {
					answer = array[i + 1] - 1;
					break;
				} answer = array[i + 1] - 1 answer array[i + 1] - 1 array[i + 1] array i + 1 i 1 1 break; System.out.println(answer) System.out.println System.out System System.out answer String[] args args public class Main {

	public static void main(String[] args) {
		// TODO 自動生成されたメソッド・スタブ
		Scanner scanner = new Scanner(System.in);
		int x1 = scanner.nextInt();
		int x2 = scanner.nextInt();
		int x3 = scanner.nextInt();
		int x4 = scanner.nextInt();
		int x5 = scanner.nextInt();
		int answer = 0;

		int [] array = new int[]{x1, x2, x3, x4, x5};
		for (int i =0; i < 5; i++) {
			boolean bool = array[i] == 0;
			if (bool == true) {
				if(i == 4) {
					answer = array[i - 1] + 1;
					break;
				} else {
					answer = array[i + 1] - 1;
					break;
				}
			}
		}

		System.out.println(answer);

	}

} public class Main {

	public static void main(String[] args) {
		// TODO 自動生成されたメソッド・スタブ
		Scanner scanner = new Scanner(System.in);
		int x1 = scanner.nextInt();
		int x2 = scanner.nextInt();
		int x3 = scanner.nextInt();
		int x4 = scanner.nextInt();
		int x5 = scanner.nextInt();
		int answer = 0;

		int [] array = new int[]{x1, x2, x3, x4, x5};
		for (int i =0; i < 5; i++) {
			boolean bool = array[i] == 0;
			if (bool == true) {
				if(i == 4) {
					answer = array[i - 1] + 1;
					break;
				} else {
					answer = array[i + 1] - 1;
					break;
				}
			}
		}

		System.out.println(answer);

	}

} Main
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		// TODO 自動生成されたメソッド・スタブ
		Scanner scanner = new Scanner(System.in);
		int x1 = scanner.nextInt();
		int x2 = scanner.nextInt();
		int x3 = scanner.nextInt();
		int x4 = scanner.nextInt();
		int x5 = scanner.nextInt();
		int answer = 0;

		int [] array = new int[]{x1, x2, x3, x4, x5};
		for (int i =0; i < 5; i++) {
			boolean bool = array[i] == 0;
			if (bool == true) {
				if(i == 4) {
					answer = array[i - 1] + 1;
					break;
				} else {
					answer = array[i + 1] - 1;
					break;
				}
			}
		}

		System.out.println(answer);

	}

}