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