Pascal's Triangle II Problem


Description

LeetCode Problem 119.

Given an integer rowIndex, return the rowIndex^th (0-indexed) row of the Pascal’s triangle.

In Pascal’s triangle, each number is the sum of the two numbers directly above it.

Example 1:

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Input: rowIndex = 3
Output: [1,3,3,1]

Example 2:

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Input: rowIndex = 0
Output: [1]

Example 3:

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Input: rowIndex = 1
Output: [1,1]

Constraints:

  • 0 <= rowIndex <= 33


Sample C++ Code

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class Solution {
public:
    vector<int> getRow(int rowIndex) {
        vector<int> A(rowIndex+1, 0);
        A[0] = 1;
        for(int i=1; i<rowIndex+1; i++)
            for(int j=i; j>=1; j--)
                A[j] += A[j-1];
        return A;
    }
};




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