LeetCode: Palindrome Partitioning

一次过

class Solution {
public:
    bool check(string s) {
        for (int i = 0; i < s.size(); i++) {
            if (s[i] != s[s.size()-1-i]) return false;
        }
        return true;
    }
    void dfs(vector<vector<string>> &ret, vector<string> &retin, string s, int beg, int size) {
        if (beg == size) ret.push_back(retin);
        for (int i = 1; i <= size-beg; i++) {
            if (check(s.substr(beg, i))) {
                retin.push_back(s.substr(beg, i));
                dfs(ret, retin, s, beg+i, size);
                retin.pop_back();
            }
        }
    }
    vector<vector<string>> partition(string s) {
        // Start typing your C/C++ solution below
        // DO NOT write int main() function
        vector<vector<string>> ret;
        vector<string> retin;
        dfs(ret, retin, s, 0, s.size());
        return ret;
    }
};

 C#

public class Solution {
    public List<List<string>> Partition(string s) {
        List<List<string>> ans = new List<List<string>>();
        List<string> tmp = new List<string>();
        dfs(ref ans, ref tmp, s, 0, s.Length);
        return ans;
    }
    public void dfs(ref List<List<string>> ans, ref List<string> tmp, string s, int beg, int size) {
        if (beg == size) {
            List<string> local = new List<string>(tmp.ToArray());
            ans.Add(local);
        }
        for (int i = 1; i <= size - beg; i++) {
            if (check(s.Substring(beg, i))) {
                tmp.Add(s.Substring(beg, i));
                dfs(ref ans, ref tmp, s, beg+i, size);
                tmp.RemoveAt(tmp.Count-1);
            }
        }
    }
    public bool check(string s) {
        for (int i = 0; i < s.Length; i++) {
            if (s[i] != s[s.Length-1-i]) return false;
        }
        return true;
    }
}