#include <stdio.h>

//function pointer
typedef int(calfun)(int *a,int *b);

int callcalfun(calfun *p,int *a,int *b){
    return (p(a,b));
}
int add(int *a,int *b){
    *a=*a+*b;
    return *a;
}

int mul(int *a,int *b){
    *a=*a**b;
    return *a;
}

int sub(int *a,int *b){
    *a=(*a)-(*b);
    return *a;
}

int main() {
    int a,b;
    scanf("%d %d",&a,&b);
    
    printf("%d\n",callcalfun(&add,&a,&b));
    printf("%d\n",callcalfun(&mul,&a,&b));
    printf("%d\n",callcalfun(&sub,&a,&b));
}

#if 0
-------------------------------------------------------------------------
int add(int *a,int *b){
    *a=*a+*b;
    return *a;
}

int mul(int *a,int *b){
    *a=*a**b;
    return *a;
}

int sub(int *a,int *b){
    *a=(*a)-(*b);
    return *a;
}

int main() {
    int a,b;
    scanf("%d %d",&a,&b);
    
    printf("%d\n",add(&a,&b));
    printf("%d\n",mul(&a,&b));
    printf("%d\n",sub(&a,&b));
}
#endif

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