《C和C指针》中转移表的实现

先上代码

#include <stdio.h>   #include <string.h>   double add(double a, double b){      return a+b;  }  double sub(double a, double b){      return a-b;  }  double mul(double a, double b){      return a*b;  }  double div(double a, double b){      return a/b;  }///////////////////////////////double (*oper_func[])(double, double) = {      add, sub, mul, div  };  int main()  {      int ifContinue=1;    int flag=1;    int oper;      double a,b;      double result; while(flag){printf("Operator:\n0:add1:sub2:mul3:div\n");  scanf("%d",&oper); if(oper>3||oper<0){printf("input wrong!\n");continue;}printf("a:");  scanf("%lf",&a);  printf("b:");  scanf("%lf",&b);  result = oper_func[oper](a, b);  printf("result is %lf\n", result); printf("Continue or not:(y/n)\n");getchar();//////////用于吃掉前面的‘回车’scanf("%c",&ifContinue);if(ifContinue=='n')flag=0;}    return 0;  }  

《C和C指针》中说转换表就是一个函数指针数组。

double (*oper_func[])(double, double) = {      add, sub, mul, div  };

默认add是0，sub是1，mul是2，div是3。