-Jarvis-'s blog

Proof needed for the wrong answer! (1200 Rated)
By -Jarvis-, history, 13 months ago, In English

I was solving a problem 2119B - Line Segments and here is approach 336217184

What is wrong with this approach?

  • Vote: I like it
  • +2
  • Vote: I do not like it

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13 months ago, hide # |
 
Vote: I like it +3 Vote: I do not like it

imagine you have two moves: a = {10, 3}.

the farthest you can get from your starting point is by moving 10 units and then 3 units in the same direction, for a total distance of 10+3=13. the closest you can end up is by moving 10 units and then moving 3 units back in the opposite direction. the final distance would be 10-3=7.

you can reach any distance between 7 and 13, but you can never end up at a distance of, say, 5 from your starting point.

your code would incorrectly say "yes" for reaching a distance of 5, because sum = 13 which is >= 5

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