HDU 1020 Train Problem I 栈和队列的应用

/*
----------------------------------------
stratege ：stack && queue &&　simulation
Theam : 给你一系列数，一次进栈，问出栈的
顺序是否符合
Author： Johnsondu
Time: 2012-04-04
type: data structure

３　１２３　－－－　２１３　　－－－》　Yes. in, in, out, out, in, out-----------------------------------------*/#include <iostream>#include <cstdio>#include <cstring>#include <algorithm>#include <stack>#include <queue>#include <cmath>#include <string>using namespace std ;char in[1000], out[1000] ;int n ;char res[1000] ;bool flag ;int main (){int i, j ;int cnt, len ;char ch, tmp ;queue <string> op ;stack <char> Q ;while (scanf ("%d %s %s", &n, in, out) != EOF){//cout << in << endl ;//cout << out << endl ;flag = true ;while (!op.empty())op.pop () ;while (!Q.empty ())Q.pop () ;cnt = 0 ;len = strlen (in) ;Q.push (in[0]) ;op.push ("in") ;for (i = 1; i < len; i ++){ch = Q.top () ;if (Q.empty ())       //火车进栈，如果栈空，直接入栈{Q.push (in[i]) ;op.push ("in") ;continue ;}if (ch == out[cnt])    //如果栈顶元素和结果一致{Q.pop () ;op.push ("out") ;   // 出栈cnt ++ ;            // out 的元素下标if (!Q.empty ())    //在此情况下，判断接下去的栈顶元素是否与当前out的值相同{tmp = Q.top () ;while (tmp == out[cnt])  //相同则继续出栈{Q.pop () ;cnt ++ ;op.push ("out") ;if (!Q.empty ())tmp = Q.top () ;elsebreak ;}}Q.push (in[i]) ;   //将当前值压入栈op.push ("in") ;}else{Q.push (in[i]) ;op.push ("in") ;}}while (!Q.empty ()){ch = Q.top () ;if (ch != out[cnt]){flag = false ;break ;}else{Q.pop () ;op.push ("out") ;cnt ++ ;}}if (flag){printf ("Yes.\n") ;while (!op.empty()){cout << op.front() << endl ;op.pop () ;}}elseprintf ("No.\n") ;printf ("FINISH\n") ;}return 0 ;}