leetcode 49. Group Anagrams【素數相乘處理字串雜湊】
阿新 • • 發佈:2018-12-17
Given an array of strings, group anagrams together.
Example:
Input: ["eat", "tea", "tan", "ate", "nat", "bat"]
,
Output:
[
["ate","eat","tea"],
["nat","tan"],
["bat"]
]
Note:
- All inputs will be in lowercase.
- The order of your output does not matter.
rt
尋找的是交換位置後字串一樣的
關鍵在於如何雜湊
查了半天
看了題解才想起來
將所有字元對應成一個素數
那麼相乘之後的值就是可以唯一表示的
class Solution { public: vector<vector<string>> groupAnagrams(vector<string>& strs) { long long num[]={2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97,101,103,107,109,113}; vector<long long>ans; vector<vector<string>> ana; for(int i=0;i<strs.size();i++){ long long tot=1; for(int j=0;j<strs[i].length();j++) tot*=num[strs[i][j]-'a']; bool flag=1; for(int j=0;j<ans.size()&&flag;j++){ if(ans[j]==tot) flag=false,ana[j].push_back(strs[i]); } // printf("tot=%lld\n",tot); if(flag==1){ ans.push_back(tot); vector<string>tmps; tmps.push_back(strs[i]); ana.push_back(tmps); } } return ana; } };