This is my A+B problem code. It accepted in 0.015 sec. How to make it faster to run in 0.001?

#include <cstdio>
int main() {
    register int a,b;
    scanf("%d %d",&a,&b);
    __asm {
        mov eax,a
        add eax,b
        mov a,eax
    }
    printf("%d",a);
    return 0;
}

And these 3725342 & 3725343 submits are the same, but has different run time.

up

It was done with an old compiler, now it's impossible.