天天向上

   1: #include "stdafx.h"

   2: #include <stdio.h>

   3: #include <iostream>

   4:  

   5: typedef double (*PtrFun)(double a, double b);

   6: using namespace std;

   7: double OperatorAdd(double a, double b);

   8: double OperatorSub(double a, double b);

   9: double OperatorMul(double a, double b);

  10: double OperatorDev(double a, double b);

  11:  

  12: int main()

  13: {

  14:     int i;

  15:     double a = 4, b = 2;

  16:     char* info[4] = { "+","-","x","/" };

  17:     PtrFun p[4]{ OperatorAdd, OperatorSub, OperatorMul, OperatorDev };

  18:     for (i = 0; i < 4; i++)

  19:     {

  20:         cout << a << info[i] << b << " = " << p[i](a, b) << endl;

  21:     }

  22:     

  23:     return 0;

  24: }

  25:  

  26: double OperatorAdd(double a, double b)

  27: {

  28:     return a + b;

  29: }

  30: double OperatorSub(double a, double b)

  31: {

  32:     return a - b;

  33: }

  34: double OperatorMul(double a, double b)

  35: {

  36:     return a*b;

  37: }

  38: double OperatorDev(double a, double b)

  39: {

  40:     double ret = (b == 0 ? 0 : a / b);

  41:     return ret;

  42: }