import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        int m = scanner.nextInt();

        int nCount = 0;
        int mCount = 0;

        if (n >= 2){
           nCount = (n * (n-1))/2;
        }
        if (m >= 2){
            mCount = (m * (m-1))/2;
        }
        System.out.println(nCount + mCount +"");
    }
} import java.util.Scanner; Scanner java.util public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        int m = scanner.nextInt();

        int nCount = 0;
        int mCount = 0;

        if (n >= 2){
           nCount = (n * (n-1))/2;
        }
        if (m >= 2){
            mCount = (m * (m-1))/2;
        }
        System.out.println(nCount + mCount +"");
    }
} Main public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        int m = scanner.nextInt();

        int nCount = 0;
        int mCount = 0;

        if (n >= 2){
           nCount = (n * (n-1))/2;
        }
        if (m >= 2){
            mCount = (m * (m-1))/2;
        }
        System.out.println(nCount + mCount +"");
    } main {
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        int m = scanner.nextInt();

        int nCount = 0;
        int mCount = 0;

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

        int nCount = 0;
        int mCount = 0;

        if (n >= 2){
           nCount = (n * (n-1))/2;
        }
        if (m >= 2){
            mCount = (m * (m-1))/2;
        }
        System.out.println(nCount + mCount +"");
    }
} public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        int m = scanner.nextInt();

        int nCount = 0;
        int mCount = 0;

        if (n >= 2){
           nCount = (n * (n-1))/2;
        }
        if (m >= 2){
            mCount = (m * (m-1))/2;
        }
        System.out.println(nCount + mCount +"");
    }
} Main
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        int m = scanner.nextInt();

        int nCount = 0;
        int mCount = 0;

        if (n >= 2){
           nCount = (n * (n-1))/2;
        }
        if (m >= 2){
            mCount = (m * (m-1))/2;
        }
        System.out.println(nCount + mCount +"");
    }
}