Self Crossing

You are given an array x of n positive numbers. You start at point (0,0) and moves x[0] metres to the north, then x[1] metres to the west, x[2] metres to the south, x[3] metres to the east and so on. In other words, after each move your direction changes counter-clockwise.

Write a one-pass algorithm with O(1) extra space to determine, if your path crosses itself, or not.

Example 1:
Given x =
[2, 1, 1, 2]
,
┌───┐
│ │
└───┼──>


Return true (self crossing)
Example 2:
Given x =
[1, 2, 3, 4]
,
┌──────┐
│ │


└────────────>

Return false (not self crossing)
Example 3:
Given x =
[1, 1, 1, 1]
,
┌───┐
│ │
└───┼>

Return true (self crossing)

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