C语言----转移表实例计算器

Posted 2021-06-24 4nc414g0n

int(*p[5])(int x, int y) = { 0, add, sub, mul, div }; //转移表

加减乘除函数

#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 div(int a, int b)
{
      return a / b;
}

主函数

int main()
{
     int x, y;
     int input = 1;
     int ret = 0;
     int(*p[5])(int x, int y) = { 0, add, sub, mul, div }; //转移表
     while (input)
     {
          printf( "*************************\\n" );
          printf( " 1:add           2:sub \\n" );
          printf( " 3:mul           4:div \\n" );
          printf( "*************************\\n" );
          printf( "请选择：" );
      scanf( "%d", &input);
          if ((input <= 4 && input >= 1))
         {
          printf( "输入操作数：" );
              scanf( "%d %d", &x, &y);
              ret = (*p[input])(x, y);
         }
          else
               printf( "输入有误\\n" );
          printf( "ret = %d\\n", ret);
     }
      return 0;
}