HDU

JAVA 练习 

package program;import java.util.*;import java.math.*;public class Main {public static void main(String[] args) {Scanner in = new Scanner(System.in);int n = in.nextInt();in.nextLine();for(int j = 0; j < n; ++j) {String s = in.nextLine();boolean f = true;if(s.charAt(0) >= '0' && s.charAt(0) <= '9') {System.out.println("no");}else{for(int i = 0; i < s.length(); ++i) {if( !( (s.charAt(i) >= '0'&& s.charAt(i) <= '9' ) || (s.charAt(i) >= 'a' && s.charAt(i) <= 'z') || s.charAt(i) == '_' || (s.charAt(i) >= 'A' && s.charAt(i) <= 'Z')) ) {//System.out.println("no");f = false;break;}}if(f) System.out.println("yes");else System.out.println("no");}}}}