题目链接:https://ac.nowcoder.com/acm/contest/3665/B
题意大概就是给你一串由flower这几个字母组成的字符串,然后让你找长度为k并且出现次数为2次以上(不包括2次)
的子串。
#include<set> #include<map> #include<stack> #include<queue> #include<cmath> #include<cstdio> #include<cctype> #include<string> #include<vector> #include<climits> #include<cstring> #include<cstdlib> #include<iostream> #include<algorithm> #include<unordered_map> #define endl '\n' #define max(a, b) (a > b ? a : b) #define min(a, b) (a < b ? a : b) #define mst(a) memset(a, 0, sizeof(a)) #define _test printf("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n") using namespace std; typedef long long ll; typedef pair<int, int> P; const double pi = acos(-1.0); const double eps = 1e-7; const int INF = 0x3f3f3f3f; const int _NAN = -0x3f3f3f3f; const int NIL = -1; const int maxn = 2e5+10; map<string, int> mark; set<string> st, ans; int main(void){ ios::sync_with_stdio(false); string s; int k; while(cin >> s >> k) { int len = s.length(); for(int i = 0; i<len-k+1; ++i) { string t = s.substr(i, k); //构造长度为k的子串 st.insert(t); //set去重 ++mark[t]; //map计数 } for (auto v : st) //c++11 新语法 if (mark[v] > 2) ans.insert(v); cout << ans.size() << endl; for (auto v : ans) cout << v << endl; st.clear();
mark.clear(); ans.clear(); } return 0; }