#include
#include
#include


int calculator(int num1, char *p, int  num2)
{
     if (p == "-a")
          return num1 + num2;
     else if (p == "-s")
          return num1 - num2;
     else if (p == "-m")
          return num1 * num2;
     else if (p == "-d")
          return num1 / num2;
     else
          return -1;
}


int main()
{
     char a;
     char *p = &a;
     int num1 = 0;
     int num2 = 0;
     scanf("%d%c%d", &num1, &a, &num2);
      

     if (a == '+')
          p = "-a";    //“-a”选项执行加法
     else if (a == '-')
          p = "-s";    //“-s”选项执行减法
     else if (a == '*')
          p = "-m";    //“-m”选项执行乘法
     else if (a == '/')
          p = "-d";    //“-d”选项执行除法
     else
          p = '\0';
           
     int ret = calculator(num1, p, num2);
     printf("%d%c%d=%d\n", num1, a, num2, ret);
     system("pause");
     return 0;
}

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