LeetCode: Pascal's Triangle

一点小失误，少数次过

class Solution {
public:
    vector<vector<int> > generate(int numRows) {
        // Start typing your C/C++ solution below
        // DO NOT write int main() function
        vector<vector<int>> ret;
        for (int i = 0; i < numRows; i++) {
            vector<int> line;
            for (int j = 0; j <= i; j++) {
                if (!j || j == i) line.push_back(1);
                else {
                    vector<int> pre = ret[i-1];
                    line.push_back(pre[j-1]+pre[j]);
                }
            }
            ret.push_back(line);
        }
        return ret;
    }
};

 C#

public class Solution {
    public List<List<int>> Generate(int numRows) {
        List<List<int>> ans = new List<List<int>>();
        for (int i = 0; i < numRows; i++) {
            List<int> line = new List<int>();
            for (int j = 0; j <= i; j++) {
                if (j == 0 || j == i) line.Add(1);
                else {
                    List<int> pre = new List<int>(ans[i-1].ToArray());
                    line.Add(pre[j-1] + pre[j]);
                }
            }
            ans.Add(line);
        }
        return ans;
    }
}