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LeetCode : 1232. Check If It Is a Straight Line

2023-08-10
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LeetCode

1232. Check If It Is a Straight Line

Problem

You are given an array coordinates, coordinates[i] = [x, y], where [x, y] represents the coordinate of a point. Check if these points make a straight line in the XY plane.

Example

Input: coordinates = [[1,2],[2,3],[3,4],[4,5],[5,6],[6,7]]
Output: true

[1] Code (23. 08. 10)

Need to Retry

n/a

Reference Code

Code 1

// Ref : https://leetcode.com/submissions/detail/964517010
class Solution {
    // Returns the delta Y.
    int getYDiff(int[] a, int[] b) {
        return a[1] - b[1];
    }
    
    // Returns the delta X.
    int getXDiff(int[] a, int[] b) {
        return a[0] - b[0];
    }
    
    public boolean checkStraightLine(int[][] coordinates) {
        int deltaY = getYDiff(coordinates[1], coordinates[0]);
        int deltaX = getXDiff(coordinates[1], coordinates[0]);
        
        for (int i = 2; i < coordinates.length; i++) {
            // Check if the slope between points 0 and i, is the same as between 0 and 1.
            if (deltaY * getXDiff(coordinates[i], coordinates[0])
                != deltaX * getYDiff(coordinates[i], coordinates[0])) {
                return false;
            }
        }
        return true;
    }
}
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Review

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Reference

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