import java.util.Scanner;

public class Main
{
	public static void main(String[] args)
	{
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int m = sc.nextInt();
		int ans = 1;
		if (n>1) {
				ans = n * (n-1) /2;
		} else {
			ans = 0;
		}

		int ans2 = 1;
		if (m>1) {
			ans2 = m * (m-1) /2;
		} else {
			ans2 = 0;
		}

		sc.close();
		System.out.println(ans+ans2);
	}
} import java.util.Scanner; Scanner java.util public class Main
{
	public static void main(String[] args)
	{
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int m = sc.nextInt();
		int ans = 1;
		if (n>1) {
				ans = n * (n-1) /2;
		} else {
			ans = 0;
		}

		int ans2 = 1;
		if (m>1) {
			ans2 = m * (m-1) /2;
		} else {
			ans2 = 0;
		}

		sc.close();
		System.out.println(ans+ans2);
	}
} Main public static void main(String[] args)
	{
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int m = sc.nextInt();
		int ans = 1;
		if (n>1) {
				ans = n * (n-1) /2;
		} else {
			ans = 0;
		}

		int ans2 = 1;
		if (m>1) {
			ans2 = m * (m-1) /2;
		} else {
			ans2 = 0;
		}

		sc.close();
		System.out.println(ans+ans2);
	} main {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int m = sc.nextInt();
		int ans = 1;
		if (n>1) {
				ans = n * (n-1) /2;
		} else {
			ans = 0;
		}

		int ans2 = 1;
		if (m>1) {
			ans2 = m * (m-1) /2;
		} else {
			ans2 = 0;
		}

		sc.close();
		System.out.println(ans+ans2);
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int n = sc.nextInt(); n sc.nextInt() sc.nextInt sc int m = sc.nextInt(); m sc.nextInt() sc.nextInt sc int ans = 1; ans 1 if (n>1) {
				ans = n * (n-1) /2;
		} else {
			ans = 0;
		} n>1 n 1 {
				ans = n * (n-1) /2;
		} ans = n * (n-1) /2 ans n * (n-1) /2 n * (n-1) n (n-1) n 1 2 {
			ans = 0;
		} ans = 0 ans 0 int ans2 = 1; ans2 1 if (m>1) {
			ans2 = m * (m-1) /2;
		} else {
			ans2 = 0;
		} m>1 m 1 {
			ans2 = m * (m-1) /2;
		} ans2 = m * (m-1) /2 ans2 m * (m-1) /2 m * (m-1) m (m-1) m 1 2 {
			ans2 = 0;
		} ans2 = 0 ans2 0 sc.close() sc.close sc System.out.println(ans+ans2) System.out.println System.out System System.out ans+ans2 ans ans2 String[] args args public class Main
{
	public static void main(String[] args)
	{
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int m = sc.nextInt();
		int ans = 1;
		if (n>1) {
				ans = n * (n-1) /2;
		} else {
			ans = 0;
		}

		int ans2 = 1;
		if (m>1) {
			ans2 = m * (m-1) /2;
		} else {
			ans2 = 0;
		}

		sc.close();
		System.out.println(ans+ans2);
	}
} public class Main
{
	public static void main(String[] args)
	{
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int m = sc.nextInt();
		int ans = 1;
		if (n>1) {
				ans = n * (n-1) /2;
		} else {
			ans = 0;
		}

		int ans2 = 1;
		if (m>1) {
			ans2 = m * (m-1) /2;
		} else {
			ans2 = 0;
		}

		sc.close();
		System.out.println(ans+ans2);
	}
} Main
import java.util.Scanner;

public class Main
{
	public static void main(String[] args)
	{
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int m = sc.nextInt();
		int ans = 1;
		if (n>1) {
				ans = n * (n-1) /2;
		} else {
			ans = 0;
		}

		int ans2 = 1;
		if (m>1) {
			ans2 = m * (m-1) /2;
		} else {
			ans2 = 0;
		}

		sc.close();
		System.out.println(ans+ans2);
	}
}
