pascals-triangle.cpp

//Given an integer numRows, return the first numRows of Pascal's triangle.
//Input: numRows = 5
//Output: [[1],[1,1],[1,2,1],[1,3,3,1],[1,4,6,4,1]]




class Solution {
public:
    vector<vector<int>> generate(int numRows) {
        vector<vector<int>> r(numRows);
        
        for(int i =0;i < numRows; i++){
            r[i].resize(i+1);
            r[i][0]=r[i][i]=1;
            
            for(int j=1;j<i;j++){
             r[i][j]=r[i-1][j-1]+r[i-1][j];   
                
            }
            
        }
        return r;
        
    }
};