#include <stdio.h>
#include <string.h>
main()
{
int n;
while(scanf("%d",&n)!=EOF)
{
int i,j,x,sum,flag[100]={0};
char a[100][100];
getchar();
for(i=0;i<n;i++)
{
gets(a[i]);
if(a[i][0]>='0' && a[i][0]<='9') //不要老是忘記‘’ (⊙ˍ⊙)
continue;
x=strlen(a[i]);
sum=0;
for(j=0;j<x;j++)
if((a[i][j]>='0' && a[i][j]<='9') || (a[i][j]>='a' && a[i][j]<='z') || (a[i][j]>='A' && a[i][j]<='Z') || a[i][j]=='_')
sum++;
if(sum==x)
flag[i]=1;
}
for(i=0;i<n;i++)
{
if(flag[i]==1)
printf("yes\n");
if(flag[i]==0)
printf("no\n");
}
}
}
默默地去翻教材看合法標識符要求