I
一次accept,dfs
class Solution { public: vector<vector<string>>v; vector<string>v1; vector<vector<string>> partition(string s) { v.clear(); if(s.size()==0)return v; v1.clear(); dfs(0,s); return v; } bool ishui(string s) { int i=0,j=s.size()-1; while(i<j) { if(s[i]==s[j]) { i++;j--; } else return false; } return true; } void dfs(int depth,string s) { if(depth==s.size()) { v.push_back(v1); } if(depth<s.size()) { for(int i=depth;i<s.size();i++) { if(ishui(s.substr(depth,i-depth+1))) { v1.push_back(s.substr(depth,i-depth+1)); dfs(i+1,s); v1.pop_back(); } } } } };
II
DFS直接导致judge large超时,采用dp,参考官网非常牛逼的解法!
class Solution { public: int minCut(string str){ int leng = str.size(); int dp[leng+1]; bool palin[leng][leng]; for(int i = 0; i <= leng; i++) dp[i] = leng-i; for(int i = 0; i < leng; i++) for(int j = 0; j < leng; j++) palin[i][j] = false; for(int i = leng-1; i >= 0; i--){ for(int j = i; j < leng; j++){ if(str[i] == str[j] && (j-i<2 || palin[i+1][j-1])){ palin[i][j] = true; dp[i] = min(dp[i],dp[j+1]+1); } } } return dp[0]-1; } };