LeetCode OJ - Pascal's Triangle

LeetCode OJ - Pascal's Triangle.cpp

class Solution {
public:
    vector<vector<int> > generate(int numRows) {
        vector<vector<int>> v;
        vector<int> n, next;
        
        if(numRows < 1)     return v;
        if(numRows >= 1){
            n.push_back(1);
            v.push_back(n);
        }
        
        if(numRows >= 2){
            n.push_back(1);//[1, 1]
            v.push_back(n);
        }
        
        if(numRows > 2){
            for(int i = 3; i <= numRows; i++){
                next.push_back(1);
                for(int j = 1; j <= i -2; j++)
                    next.push_back(n[j-1] + n[j]);
                next.push_back(1);
                n = next;
                next.clear();
                v.push_back(n);
            }    
        }
        return v;
    }
};