#include <stdio.h>

#include <math.h>

double calc(double (*funp)(double), double a, double b); /*函数原型说明 */

double f1(double x), f2(double x);

int main() {

double result;

double (*funp)(double);

result = calc(f1, 0.0, 1.0); /* 函数名f1作为函数calc的实参 */

printf("1: resule=%.4f\n", result);

funp = f2; /* 对函数指针funp赋值 */

result = calc(funp, 1.0, 2.0); /* 函数指针funp作为函数calc的实参 */

printf("2: resule=%.4f\n", result);

return 0;

}

double calc(double (*funp)(double), double a, double b) {

double z;

z = (b - a) / 2 * ((*funp)(a) + (*funp)(b)); /* 调用funp指向的函数 */

return (z);

}

double f1(double x) {

return (x * x);

}

double f2(double x) {

return (sin(x) / x);

}