LeetCode Hot 100 P118 Pascal's Triangle

---

Timeline

Timeline

2026-03-20

init

Dynamic Programming

---

Problem:

P118 Pascal's Triangle

https://leetcode.cn/problems/pascals-triangle/description/?envType=study-plan-v2&envId=top-100-liked

#include <vector>
using std::vector;

class Solution {
    public:
        vector<vector<int> > generate(int numRows)
        {
                int i, j, n;
                int last = 0;
                vector<vector<int> > res;

                res.push_back({ 1 });
                if (numRows == 1)
                        return res;

                for (i = 1; i < numRows; i++) {
                        vector<int> &last_line = res.back();
                        vector<int> curr;

                        last = 0;
                        n = last_line.size();

                        for (j = 0; j < n; j++) {
                                curr.push_back(last_line[j] + last);
                                last = last_line[j];
                        }

                        curr.push_back(1);

                        res.push_back(curr);
                }

                return res;
        }
};