#include<stdio.h>
int main(void){
    int a,b,i1=0,i2=0,i,j;
    scanf("%d%d",&a,&b);
    if(a==0&&b==0)
    printf("0\n");
    for(int p=0;a==i1;++i1){
        ++p;
    }
    for(int p=0;b==i2;++i2){
        ++p;
    }
    i=i1>i2?i2:i1;
    j=i1>i2?i1:i2;
    double ans=(2*j*j*j-2*i*i*i+3*a*b*b-3*a*j*j-3*b*j*j+3*a*i*i+3*b*i*i-3*a*b*b)/6;
    printf("%f\n",ans);
    return 0;
}