sdut 2163:Identifiers（第二届山东省省赛原题，水题）

Identifiers

Time Limit: 1000ms Memory limit: 65536K 有疑问？点这里^_^

题目描述

Identifier is an important concept in the C programming language. Identifiers provide names for several language elements, such as functions, variables, labels, etc.
An identifier is a sequence of characters. A valid identifier can contain only upper and lower case alphabetic characters, underscore and digits, and must begin with an alphabetic character or an underscore. Given a list of chararcter sequences, write a program to check if they are valid identifiers.

输入

The first line of the input contains one integer, N, indicating the number of strings in the input. N lines follow, each of which contains at least one and no more than 100 characters. (only upper and lower case alphabetic characters, digits, underscore (" "), hyphen ("-"), period ("."), comma (","), colon (":"), semicolon (";"), exclamation mark ("!"), question mark ("?"), single and double quotation marks, parentheses, white space and square brackets may appear in the character sequences.)

输出

For each of the N lines, output "Yes" (without quote marks) if the character sequence contained in that line make a valid identifier; output "No" (without quote marks) otherwise.

示例输入

7
ValidIdentifier
valid_identifier
valid_identifier
0_invalid_identifier
1234567
invalid identifier
adefhklmruvwxyz12356790_-.,:;!?'"()[]ABCDGIJLMQRSTVWXYZ

示例输出

Yes
Yes
Yes
No
No
No
No

提示

来源

山东省第二届ACM大学生程序设计竞赛

　　水题。
　　代码：

#include <iostream>
#include <stdio.h>
using namespace std;

int main()
{
int i,j,n;
cin>>n;
getchar();
for(i=1;i<=n;i++){
char a[110];
cin.getline(a,110,'\n');
if(('a'<=a[0] && a[0]<='z') || ('A'<=a[0] && a[0]<='Z') || a[0]=='_'){
for(j=0;a[j];j++)
if(!(('a'<=a[j] && a[j]<='z') ||
('A'<=a[j] && a[j]<='Z') ||
('0'<=a[j] && a[j]<='9') ||
a[j]=='_') )
break;
if(a[j])
cout<<"No"<<endl;
else
cout<<"Yes"<<endl;
}
else
cout<<"No"<<endl;
}
return 0;
}

/**************************************
Problem id    : SDUT OJ 2163
User name    : Miracle
Result        : Accepted
Take Memory    : 452K
Take Time    : 0MS
Submit Time    : 2014-04-20 09:18:49
**************************************/

Freecode : www.cnblogs.com/yym2013