标签：img cte cas phi 依次 ram set long 第一个字符
Petya recieved a gift of a string s with length up to 105 characters for his birthday. He took two more empty strings t and u and decided to play a game. This game has two possible moves:
Petya wants to get strings s and t empty and string u lexicographically minimal.
You should write a program that will help Petya win the game.
First line contains non-empty string s (1?≤?|s|?≤?105), consisting of lowercase English letters.
Print resulting string u.
开一个26字母的数组来方便的管理当前s里最小的字符
然后每次将s的第一个字符入栈，如果栈顶比s剩下的字符都小就出栈直到不满足这个情况或栈空。
s入完后，把所有栈内的元素依次出栈
#include <cstdio> #include <cmath> #include <cctype> #include <iostream> #include <cstring> #include <algorithm> #include <string> #include <stack> #include <vector> #include <map> #include <set> using namespace std; typedef long long LL; string s; int ch[29] = {0}; stack<char> st; int main() { // freopen("test.in","r",stdin); ios::sync_with_stdio(false); cin >> s; int len = s.length(); for (int i=0;i<len;i++){ ch[s[i] - ‘a‘] ++; } int now = 0; while (ch[now] == 0 && now <= 25){ now ++; } for (int i=0;i<len;i++){ ch[s[i] - ‘a‘] --; if (s[i] != now + ‘a‘){ st.push(s[i]); } else { cout << s[i]; } while (ch[now] == 0 && now <= 25){ now ++; } while (!st.empty() && st.top() <= now + ‘a‘){ cout << st.top(); st.pop(); } } while (!st.empty()){ cout << st.top(); st.pop(); } return 0; }
Codeforces 797C. Minimal string
标签：img cte cas phi 依次 ram set long 第一个字符
原文地址：http://www.cnblogs.com/ToTOrz/p/7270227.html
