不少程序员都会碰到的三个面试题

面试问题如下：

1. 求从10到100中能被3或5整除的数的和

int sum = 0; for(int i = 10; i <= 100; i++) if( i % 3 == 0 || i % 5 == 0) sum += i; System.out.println(sum);

2. 将一个字符串逆序，不要使用反转函数

String message = \"he saw a racecar\";

StringBuilder rev = new StringBuilder();

for(int i = message.length()-1; i >= 0; i--)

rev.append(message.charAt(i));

System.out.println(rev.toString());

3. 反转一个栈

import java.util.*;
public class MyProgram extends com.ktbyte.submit.Coder {
public static void main(String[] args) {
Stack items = new Stack();
items.push(\"he\");      //he is at the bottom of the stack
items.push(\"saw\");
items.push(\"a\");
items.push(\"racecar\");
reverseStack(items);   //now he is at the top

//print in order pushed:
while(items.size()>0) System.out.println(items.pop());
}

public static  void reverseStack(Stack stack) {
Queue rev = new LinkedList();
while(stack.size()>0) rev.offer(stack.pop());
while(rev.size()>0)   stack.push(rev.poll());
}
}