UVa11488-Hyper Prefix Sets（trie树）

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H	Hyper Prefix Sets

　　 　　Prefix goodness of a set string is length of longest common prefix*number of strings in the set. For example the prefix goodness of the set {000,001,0011} is 6.You are given a set of binary strings. Find the maximum prefix goodness among all possible subsets of these binary strings. 　　Input First line of the input contains T(≤20) the number of test cases. Each of the test cases start with n(≤50000) the number of strings. Each of the next n lines contains a string containing only 0 and 1. Maximum length of each of these string is 200. 　　Output For each test case output the maximum prefix goodness among all possible subsets of n binary strings. Sample Input Output for Sample Input

4 　　4 　　0000 　　0001 　　10101 　　010 　　2 　　01010010101010101010 　　11010010101010101010 　　3 　　010101010101000010001010 　　010101010101000010001000 　　010101010101000010001010 　　5 　　01010101010100001010010010100101 　　01010101010100001010011010101010 　　00001010101010110101 　　0001010101011010101 　　00010101010101001

6 　　20 　　66 　　44

　　Problem Setter : Abdullah Al Mahmud Special Thanks : Manzurur Rahman Khan 　　 　　 　　 　　 　　#include #include #include #include #include #include #include using namespace std; const int maxn = 5000000; vector vs; int cnt,ans,n; int ch[maxn][2]; int val[maxn]; inline int getIdx(char a){ return a-'0'; } void insert(string st){ int u = 0; for(int i = 0; i < st.size(); i++){ int k = getIdx(st); if(!ch[k]){ memset(ch[cnt],0,sizeof ch[cnt]); val[cnt]++; ans = max(ans,val[cnt]*(i+1)); ch[k] = cnt++; }else{ val[ch[k]]++; ans = max(ans,val[ch[k]]*(i+1)); } u = ch[k]; } } int main(){ int ncase; cin >> ncase; while(ncase--){ vs.clear(); memset(val,0,sizeof val); memset(ch[0],0,sizeof ch[0]); cnt = 1; ans = 0; cin >> n; while(n--){ string st; cin >> st; insert(st); } cout SO娱乐城：真_人.足球.彩票齐全| 开户送10元.首存送58元.手机可投ち注任何游戏顶级信用ち提现即时到账SO.CC