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();
    System.out.println(N * (N - 1) / 2 + M * (M - 1) / 2);}
} 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();
    System.out.println(N * (N - 1) / 2 + M * (M - 1) / 2);}
} Main public static void main(String...args) {
    Scanner sc = new Scanner(System.in); int N = sc.nextInt(); int M = sc.nextInt();
    System.out.println(N * (N - 1) / 2 + M * (M - 1) / 2);} main {
    Scanner sc = new Scanner(System.in); int N = sc.nextInt(); int M = sc.nextInt();
    System.out.println(N * (N - 1) / 2 + M * (M - 1) / 2);} 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 System.out.println(N * (N - 1) / 2 + M * (M - 1) / 2) System.out.println System.out System System.out N * (N - 1) / 2 + M * (M - 1) / 2 N * (N - 1) / 2 N * (N - 1) N (N - 1) N 1 2 M * (M - 1) / 2 M * (M - 1) M (M - 1) M 1 2 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();
    System.out.println(N * (N - 1) / 2 + M * (M - 1) / 2);}
} public class Main { public static void main(String...args) {
    Scanner sc = new Scanner(System.in); int N = sc.nextInt(); int M = sc.nextInt();
    System.out.println(N * (N - 1) / 2 + M * (M - 1) / 2);}
} 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();
    System.out.println(N * (N - 1) / 2 + M * (M - 1) / 2);}
}