zoj 1259 Rails

//这题对输入输出格式有比较严格的要求，运用到二重循环来很好地解决了问题！#include "iostream"#include "stack"#include "memory.h"using namespace std;int train[1010];int main(){stack<int> s;int num, i, A, B, tag;while (cin >> num && num)//对第一个输入是否为0的判断！{memset(train, 0, sizeof(train));while (cin >> train[1] && train[1])//对第二个输入是否为0的判断！{A = B = 1, tag = 1;for (i = 2; i <= num; i++)cin >> train[i];while (B <= num){if (A == train[B]){A++;B++;}else if (!s.empty() && train[B] == s.top()){s.pop();B++;}else if (A <= num){s.push(A);A++;}else {tag = 0;break;}}if (tag)cout << "Yes" << endl;elsecout << "No" << endl;}cout << endl;}}