#include <stdio.h>
main(){
int x;
int y;
scanf("%d %d",&x,&y);
printf("%d\n",x%y);
}
#include <stdio.h>
main(){
int a;
int b;
int c;
scanf("%d %d %d",&a,&b,&c);
printf("%d\n",a*(b+c-a));
}
#include <stdio.h>
main(){
int x;
scanf("%d",&x);
printf("%d\n",x*x+2*x+5);
}
#include<stdio.h>
main(){
float r;
scanf("%f",&r);
printf("%f\n",r*r*3.14159);
}