简单程序和表达式

/*编一个可由用户键入简单表达式的程序，形式如下：number operater number该程序要计算该表达式并以两位小数显示结果。要识别的运算符operator为加、减、乘、除。*/

#include "stdafx.h"

/*int main(int argc, char* argv[]){ float value1,value2; char operater;  printf("Input your expression:/n");  scanf("%f%c%f",&value1,&operater,&value2); if(operater='+')  printf("%2f/n",value1+value2); else if(operater='-')  printf("%2f/n",value1-value2); else if(operater='*')  printf("%2f/n",value1*value2); else if(operater='/')  if(value2=0.0)   printf("Division by zero/n");  else   printf("%2f/n",value1/value2); else  printf("Unknown operater/n"); return 0;}*//*输入123.5+59.3结果为182.80输入198.710 结果为Division by zero输入125$28结果为Unknown operater*///用switch语句来实现void main(){ float value1,value2; char operater;  printf("Input your expression:/n");  scanf("%f%c%f",&value1,&operater,&value2);  switch(operater)  {  case'+':printf("%2f/n",value1+value2);    break;  case'-':printf("%2f/n",value1-value2);    break;  case'*':printf("%2f/n",value1*value2);    break;  case'/':if(value2=0.0)     printf("Division by zero/n");    else     printf("%2f/n",value1/value2);    break;  default:    printf("Unknown operater/n");  }}