标签:不用 integer lightoj cstring ini longest nbsp max Fix
Given a set of n DNA samples, where each sample is a string containing characters from {A, C, G, T}, we are trying to find a subset of samples in the set, where the length of the longest common prefix multiplied by the number of samples in that subset is maximum.
To be specific, let the samples be:
ACGT
ACGTGCGT
ACCGTGC
ACGCCGT
If we take the subset {ACGT} then the result is 4 (4 * 1), if we take {ACGT, ACGTGCGT, ACGCCGT} then the result is 3 * 3 = 9 (since ACG is the common prefix), if we take {ACGT, ACGTGCGT, ACCGTGC, ACGCCGT} then the result is 2 * 4 = 8.
Now your task is to report the maximum result we can get from the samples.
Input
Input starts with an integer T (≤ 10), denoting the number of test cases.
Each case starts with a line containing an integer n (1 ≤ n ≤ 50000) denoting the number of DNA samples. Each of the next n lines contains a non empty string whose length is not greater than 50. And the strings contain characters from {A, C, G, T}.
Output
For each case, print the case number and the maximum result that can be obtained.
Sample Input
3
4
ACGT
ACGTGCGT
ACCGTGC
ACGCCGT
3
CGCGCGCGCGCGCCCCGCCCGCGC
CGCGCGCGCGCGCCCCGCCCGCAC
CGCGCGCGCGCGCCCCGCCCGCTC
2
CGCGCCGCGCGCGCGCGCGC
GGCGCCGCGCGCGCGCGCTC
Sample Output
Case 1: 9
Case 2: 66
Case 3: 20
Note
Dataset is huge. Use faster I/O methods.
字典树,不过一共只有四个字母,所以映射四个连续位置,不用每个点都有26个儿子。
代码:
#include <iostream> #include <cstdio> #include <sstream> #include <cstring> using namespace std; int n,m,t,pos; int trie[2000001][4],pre[2000001]; int to[26]; void Insert(string s) { int i = 0,c = 0,len = s.size(); while(i < len) { int d = to[s[i] - ‘A‘]; if(!trie[c][d]) { trie[c][d] = ++ pos; } c = trie[c][d]; pre[c] ++; m = max(m,pre[c] * (i + 1)); i ++; } } int main() { to[‘C‘ - ‘A‘] = 1; to[‘G‘ - ‘A‘] = 2; to[‘T‘ - ‘A‘] = 3; scanf("%d",&t); char s[51]; for(int i = 1;i <= t;i ++) { memset(pre,0,sizeof(pre)); m = 0; scanf("%d",&n); for(int j = 0;j < n;j ++) { scanf("%s",s); Insert(s); } printf("Case %d: %d\n",i,m); } }
标签:不用 integer lightoj cstring ini longest nbsp max Fix
原文地址:https://www.cnblogs.com/8023spz/p/9597545.html