import java.io.*;
import java.util.*;
 
class Test{
    public static void main(String args[]){
        Stack stack = new Stack();
 
        // push
        for( int i = 0 ; i < 5 ; i++ ){
            Integer integer = new Integer(i);
            stack.push(integer);
            System.out.println( "push : " + integer );
        }
 
        // 改行
        System.out.println();
 
        // pop
        while( !stack.empty() )
            System.out.println( "pop : " + stack.pop() );
    }
}
 
 

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