c++语言问题missing function header (old-style formal list?)

来源：百度知道 编辑：UC知道 时间：2024/09/28 14:20:11
#include<iostream>
using namespace std;
int main()
switch(grade);
{case'A':cout<<"90~100\n";break;
case'B':cout<<"80~89\n";break;
case'C':cout<<"70~79\n";break;
case'D':cout<<"60~69\n";break;
case'E':cout<<"<60\n";break;
default:cout<<"error\n";break;
}

这个哪错了？在线等！！！
还是有错！！！warning C4508: 'main' : function should return a value; 'void' return type assumed
执行 cl.exe 时出错.

#include<iostream>
using namespace std;
int main() { //这少了{
char grade;
cout<<"Input grade:";
cin>>grade; //grade未定义
switch(grade);
{case'A':cout<<"90~100\n";break;
case'B':cout<<"80~89\n";break;
case'C':cout<<"70~79\n";break;
case'D':cout<<"60~69\n";break;
case'E':cout<<"<60\n";break;
default:cout<<"error\n";break;
}
return 0; ////这少了return
}//这少了}

//改一下，这样比较完整一点
#include<iostream>
using namespace std;
int main()
{
char grade;
cout<<"Input:"<<endl;
grade=getchar();

while(grade!='X')
{

switch(grade)
{case'A':cout<<"90~100\n";break;
case'B':cout&l