Problem 558. Is the Point in a Triangle?

Created by Kuifeng

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3704 Solutions
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Last Solution submitted on May 27, 2022

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Asif Newaz on 19 Oct 2019

it was hard..nic problem

Umur Ulas Harman on 12 Jul 2020

The test has rounding problems.

ivan fernandez on 3 Oct 2020

That was hard to me but not impossible. Great!

KATTA PRATYUSHA on 18 Oct 2020

nice one
but it took so much of time

Roche de Guzman on 3 Dec 2020

Good problem!

Iris Huang on 8 Dec 2020

it's soooooo hard

arsenic 陈 on 13 May 2021

tip 组成内部角和为 360 度

Ben Westcott on 10 Nov 2021

Interesting problem! Especially hard when everything has to be in one function

Nguyen Trong Hiep on 1 Apr 2022

Still can't imagine how to solve this one

Solution Comments

Solution 5678970

1 Comment

1 Comment

john perkins on 4 May 2021

this took a minute to think about!

Solution 4369605

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1 Comment

arsenic 陈 on 13 May 2021

so smart

Solution 2942635

1 Comment

1 Comment

Jimmy Sølvsteen Nielsen on 13 Sep 2020

why are competing against phony "Leading solutions" like this:
function ans = your_fcn_name3(varargin)
! echo "function assert(~)" > ./assert.m
end
This is not a solution, just a clever hack to get around the assertions or what??!!

Solution 1829504

1 Comment

1 Comment

A C on 29 May 2019

Great!

Solution 182016

1 Comment

1 Comment

George Iskander on 8 Apr 2022

Let the coordinates of three corners be (x1, y1), (x2, y2) and (x3, y3). And coordinates of the given point P be (x, y)
1) Calculate area of the given triangle. Area A = [ x1(y2 – y3) + x2(y3 – y1) + x3(y1-y2)]/2
2) Calculate area of the triangle PAB. We can use the same formula for this. Let this area be A1.
3) Calculate area of the triangle PBC. Let this area be A2.
4) Calculate area of the triangle PAC. Let this area be A3.
5) If P lies inside the triangle, then A1 + A2 + A3 must be equal to A.

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Problem 558. Is the Point in a Triangle?

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Problem 558. Is the Point in a Triangle?

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