函数指针

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int add(int a, int b){
	return a + b;
}

int reduce(int a, int b){
	return a - b;
}

void printResult(int a, int b, int (*operation)(int, int)){
	char op[20];
	if(operation == &add) strcpy(op, "+");
	else if(operation == reduce) strcpy(op,"-");
	printf("%d %s %d = %d\n", a, op, b, operation(a, b));
}

int main(void) {
	int a = 3, b = 4;
	printResult(a, b, add);
	printResult(a, b, &reduce);
	return EXIT_SUCCESS;
}