56. Function Pointer Dispatch Table

#include <stdio.h>

int add(int a, int b) { return a + b; }
int sub(int a, int b) { return a - b; }
int mul(int a, int b) { return a * b; }
int divide(int a, int b) { return a / b; }

#define ADD 0
#define SUB 1
#define MULT 2
#define DIV 3

int (* op[4])(int a, int b) = {add, sub, mul, divide};
int execute_command(int a, int b, int cmd) {
    if (cmd == ADD){
        return op[ADD](a,b);
    }
    if (cmd == SUB){
        return op[SUB](a,b);
    }
    if (cmd == MULT){
        return op[MULT](a,b);
    }
    if ((cmd == DIV)& (b!=0)){
        return op[DIV](a,b);
    }else{
    
    return 0;
    }
}

int main() {
    int a, b, cmd;
    scanf("%d %d %d", &a, &b, &cmd);

    int result = execute_command(a, b, cmd);
    printf("%d", result);

    return 0;
}

Solving Approach