335. Self Crossing

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Problem

You are given an array of integers distance.

You start at point (0,0) on an X-Y plane and you move distance[0] meters to the north, then distance[1] meters to the west, distance[2] meters to the south, distance[3] meters to the east, and so on. In other words, after each move, your direction changes counter-clockwise.

Return true if your path crosses itself, and false if it does not.

Example 1:

Input: distance = [2,1,1,2]
Output: true

Example 2:

Input: distance = [1,2,3,4]
Output: false

Example 3:

Input: distance = [1,1,1,1]
Output: true

Code

class Solution {
    public boolean isSelfCrossing(int[] x) {
        for(int i = 3; i < x.length; i++){
            if(x[i] >= x[i - 2] && x[i - 3] >= x[i - 1]){
                return true;
            }
            
            if(i >= 4 && x[i - 1] == x[i - 3] && x[i] >= x[i - 2] - x[i - 4]){
                return true;
            }
            
            if(i >= 5 
               && x[i - 2] >= x[i - 4] 
               && x[i - 3] >= x[i - 1] 
               && x[i - 1] >= x[i - 3] - x[i - 5]
               && x[i] >= x[i - 2] - x[i - 4]){
                return true;
            }
        }
        
        return false;
    }
}