Description
https://oj.leetcode.com/submissions/detail/12004124/
Difficulty: 2.0/5.0 star
Related: https://oj.leetcode.com/problems/pascals-triangle-ii/
Solution
Here we use pascals-triangle-ii as a subprocess which speeds up the compution. It finishes in 4ms in leetcode OJ.
class Solution {
public:
vector<vector<int> > generate(int numRows) {
vector<vector<int> > pascalTriangle;
if (!numRows)
return pascalTriangle;
vector<int>curLayer; curLayer.push_back(1);
pascalTriangle.push_back(curLayer);
for (int i = 1; i < numRows; ++ i){
for (int j = i; j > 0; -- j)
curLayer[j] += curLayer[j-1];
curLayer.push_back(1);
pascalTriangle.push_back(curLayer);
}
return pascalTriangle;
}
};