hdu2024C语言合法标识符

#include<iostream>
#include<stdio.h>
#include<math.h>
#include<stdlib.h>
#include<string.h>
#include<limits>
using namespace std;

int main()
{
//freopen("in.txt","r",stdin);
int n;
char a[60];
cin>>n;
getchar();
while(n--)
{
gets(a);
int flag=0;
for(int i=0;i<strlen(a);i++)
{
if(a[i]=='_' || (a[i]>='0' && a[i]<='9') || (a[i]>='A' && a[i]<='Z') || (a[i]>='a' && a[i]<='z') )
{
if(i==0 && (a[i]>='0' && a[i]<='9'))
{
flag=1;
break;
}
continue;
}
else
{
flag=1;
break;
}
}
if(flag)
cout<<"no"<<endl;
else
cout<<"yes"<<endl;
}
return 0;
}