loading...

Daily Challenge #84 - Third Angle of a Triangle

twitter logo ・1 min read

Daily Challenge (159 Part Series)

1) Daily Challenge #1 - String Peeler 2) Daily Challenge #2 - String Diamond 3 ... 157 3) Daily Challenge #3 - Vowel Counter 4) Daily Challenge #4 - Checkbook Balancing 5) Daily Challenge #5 - Ten Minute Walk 6) Daily Challenge #6 - Grandma and her friends 7) Daily Challenge #7 - Factorial Decomposition 8) Daily Challenge #8 - Scrabble Word Calculator 9) Daily Challenge #9 - What's Your Number? 10) Daily Challenge #10 - Calculator 11) Daily Challenge #11 - Cubic Numbers 12) Daily Challenge #12 - Next Larger Number 13) Daily Challenge #13 - Twice Linear 14) Daily Challenge #14 - Square into Squares 15) Daily Challenge #15 - Stop gninnipS My sdroW! 16) Daily Challenge #16 - Number of People on the Bus 17) Daily Challenge #17 - Double Trouble 18) Daily Challenge #18 - Triple Trouble 19) Daily Challenge #19 - Turn numbers into words 20) Daily Challenge Post #20 - Number Check 21) Daily Challenge #21 - Human Readable Time 22) Daily Challenge #22 - Simple Pig Latin 23) Daily Challenge #23 - Morse Code Decoder 24) Daily Challenge #24 - Shortest Step 25) Daily Challenge #25 - Double Cola 26) Daily Challenge #26 - Ranking Position 27) Daily Challenge #27 - Unlucky Days 28) Daily Challenge #28 - Kill the Monster! 29) Daily Challenge #29 - Xs and Os 30) Daily Challenge #30 - What is the price? 31) Daily Challenge #31 - Count IPv4 Addresses 32) Daily Challenge #32 - Hide Phone Numbers 33) Daily Challenge #33 - Did you mean...? 34) Daily Challenge #34 - WeIrD StRiNg CaSe 35) Daily Challenge #35 - Find the Outlier 36) Daily Challenge #36 - Let's go for a run! 37) Daily Challenge #37 - Name Swap 38) Daily Challenge #38 - Middle Name 39) Daily Challenge #39 - Virus 40) Daily Challenge #40 - Counting Sheep 41) Daily Challenge #41 - Greed is Good 42) Daily Challenge #42 - Caesar Cipher 43) Daily Challenge #43 - Boardgame Fight Resolver 44) Daily Challenge #44 - Mexican Wave 45) Daily Challenge #45 - Change Machine 46) Daily Challenge #46 - ??? 47) Daily Challenge #47 - Alphabets 48) Daily Challenge #48 - Facebook Likes 49) Daily Challenge #49 - Dollars and Cents 50) Daily Challenge #50 - Number Neighbor 51) Daily Challenge #51 - Valid Curly Braces 52) Daily Challenge #52 - Building a Pyramid 53) Daily Challenge #53 - Faro Shuffle 54) Daily Challenge #54 - What century is it? 55) Daily Challenge #55 - Building a Pile of Cubes 56) Daily Challenge #56 - Coffee Shop 57) Daily Challenge #57 - BMI Calculator 58) Daily Challenge #58 - Smelting Iron Ingots 59) Daily Challenge #59 - Snail Sort 60) Daily Challenge #60 - Find the Missing Letter 61) Daily Challenge #61 - Evolution Rate 62) Daily Challenge #62 - Josephus Survivor 63) Daily Challenge #63- Two Sum 64) Daily Challenge #64- Drying Potatoes 65) Daily Challenge #65- A Disguised Sequence 66) Daily Challenge #66- Friend List 67) Daily Challenge #67- Phone Directory 68) Daily Challenge #68 - Grade Book 69) Daily Challenge #69 - Going to the Cinema 70) Daily Challenge #70 - Pole Vault Competition Results 71) Daily Challenge #71 - See you next Happy Year 72) Daily Challenge #72 - Matrix Shift 73) Daily Challenge #73 - ATM Heist 74) Daily Challenge #74 - Free Pizza 75) Daily Challenge #75 - Set Alarm 76) Daily Challenge #76 - Bingo! (or not...) 77) Daily Challenge #77 - Bird Mountain 78) Daily Challenge #78 - Number of Proper Fractions with Denominator d 79) Daily Challenge #79 - Connect Four 80) Daily Challenge #80 - Longest Vowel Change 81) Daily Challenge #81 - Even or Odd 82) Daily Challenge #82 - English Beggars 83) Daily Challenge #83 - Deodorant Evaporator 84) Daily Challenge #84 - Third Angle of a Triangle 85) Daily Challenge #85 - Unwanted Dollars 86) Daily Challenge #86 - Wouldn't, not Would. 87) Daily Challenge #87 - Pony Express 88) Daily Challenge #88 - Recursive Ninjas 89) Daily Challenge #89 - Extract domain name from URL 90) Daily Challenge #90 - One Step at a Time 91) Daily Challenge #91 - Bananas 92) Daily Challenge #92 - Boggle Board 93) Daily Challenge #93 - Range Extraction 94) Daily Challenge #94 - Last Digit 95) Daily Challenge #95 - CamelCase Method 96) Daily Challenge #96 - Easter Egg Crush Test 97) Daily Challenge #97 - Greed is Good 98) Daily Challenge #98 - Make a Spiral 99) Daily Challenge #99 - Balance the Scales 100) Daily Challenge #100 - Round Up 101) Daily Challenge #101 - Parentheses Generator 102) Daily Challenge #102 - Pentabonacci 103) Daily Challenge #103 - Simple Symbols 104) Daily Challenge #104 - Matrixify 105) Daily Challenge #105 - High-Sum Matrix Drop 106) Daily Challenge #106 - Average Fuel Consumption 107) Daily Challenge #107 - Escape the Mines 108) Daily Challenge #108 - Find the Counterfeit Coin 109) Daily Challenge #109 - Decorate with Wallpaper 110) Daily Challenge #110 - Love VS. Friendship 111) Daily Challenge #111 - 99 Bottles of Beer 112) Daily Challenge #112 - Functions of Integers on the Cartesian Plane 113) Daily Challenge #113 - Iterative Rotation Cipher 114) Daily Challenge #114 - Speed Control 115) Daily Challenge #115 - Look and Say Sequence 116) Daily Challenge #116 - Shortest Knight Path 117) Daily Challenge #117 - MinMinMax 118) Daily Challenge #118 - Reversing a Process 119) Daily Challenge #119 - Adding Big Numbers 120) Daily Challenge #120 - Growth of a Population 121) Daily Challenge #121 - Who has the most money? 122) Daily Challenge #122 - Clockwise Spirals 123) Daily Challenge #123 - Curry me Softly 124) Daily Challenge #124 - Middle Me 125) Daily Challenge #125 - 23 Matches or More 126) Daily Challenge #126 - The Supermarket Line 127) Daily Challenge #127 - Playing with Passphrases 128) Daily Challenge #128 - Blackjack Scorer 129) Daily Challenge #129 - Clay Pigeon Shooting 130) Daily Challenge #130 - GCD Sum 131) Daily Challenge #131 - Remove Anchor from URL 132) Daily Challenge #132 - Is my friend cheating? 133) Daily Challenge #133 - Suitcase Packing 134) Daily Challenge #134 - Rice and Chessboard Problem 135) Daily Challenge #135 - The Wide Mouthed Frog! 136) Daily Challenge #136 - The Deaf Rats of Hamelin 137) Daily Challenge #137 - Help the Bookseller 138) Daily Challenge #138 - Do I get a Bonus? 139) Daily Challenge #138 - Keep Up the Hoop 140) Daily Challenge #140 - I love you, a little, a lot, passionately ... not at all 141) Daily Challenge #141 - Two Sum 142) Daily Challenge #142 - Parts of a Whole 143) Daily Challenge #143 - Big Arithmetic 144) Daily Challenge #144 - Box Office Clerk 145) Daily Challenge #145 - SET Card Game 146) Daily Challenge #146 - The Dollar Game 147) Daily Challenge #147 - NIM 148) Daily Challenge #148 - Disemvowel Trolls 149) Daily Challenge #149 - Fun with Lamps 150) Daily Challenge #150 - Boggle Guess Validator 151) Daily Challenge #151 - Reverse Parentheses 152) Daily Challenge #152 - Strongest Number in an Interval 153) Daily Challenge #153 - Horse Race Gamble 154) Daily Challenge #154 - Stable Arrangement 155) Daily Challenge #155 - Royal Arranged Marriages 156) Daily Challenge #162 - Taxi Dispatching 157) Daily Challenge #163 - Significant Figures 158) Daily Challenge #164 - Jump 159) Daily Challenge #165 - Password Lost in a Grid

You are given two angles of a triangle in degrees.

Write a function to return the third angle. Only positive integers will be tested.

Sample Tests:

thirdAngle(30, 60)
thirdAngle(60, 60)
thirdAngle(43, 78)
thirdAngle(10, 20)


This challenge comes from user5651159. Thank you to CodeWars, who has licensed redistribution of this challenge under the 2-Clause BSD License!

Want to propose a challenge idea for a future post? Email yo+challenge@dev.to with your suggestions!

twitter logo DISCUSS (15)
markdown guide
 

ANSI C

#include <math.h>

double third_angle ( double first_angle , double second_angle ) {
    first_angle = fmod( first_angle , 360.0 );  // Get absolute
    second_angle = fmod( second_angle , 360.0 );

    if ( first_angle + second_angle >= 180 )
        return 0.0;  // That's not a triangle! OwO

    return ( 180 - first_angle - second_angle );
}

int main ( int argc , char ** argv ) {
    if ( 
        ( int ) third_angle( 30 , 60 ) == 90 &&
        ( int ) third_angle( 60 , 60 ) == 60 &&
        ( int ) third_angle( 43 , 78 ) == 59 &&
        ( int ) third_angle( 10 , 20 ) == 150 )
            return 0;  // It works!

    return 101;  // Or not
}

Run with ~$ gcc -lm <file_name> && ./a.out

 

My solution in js

const thirdAngle = (angle1, angle2) => (angle1 && angle2 && (angle3 = 180 - (angle1 + angle2)) > 0) ? angle3 : 'Invalid - Sum of all angles of a triangle should be 180 degrees';
 

What happens if I enter thirdAngle(0,0)?

 

Good catch. Edited. But the challenge is to deal with positive integers so didn't take 0 into account as it is neither positive nor negative integer.

True enough. But why code purely for specs when coding for the edge and error cases takes just a few more minutes?

 

Solution in APL

(using Dyalog APL)

thirdAngle←{r←180-+/⍡ β‹„ (r<0)∨0∊⍡: 'This is not a triangle!' β‹„ r}

Tests:

      thirdAngle 30 60
90
      thirdAngle 60 60
60
      thirdAngle 43 78
59
      thirdAngle 10 20
150

Try it online!

 

Elm

import List exposing (all, sum)
import Maybe exposing (andThen, map)


isAngle : Int -> Bool
isAngle angle =
    angle > 0 && angle < 180


maybeAngles : List Int -> Maybe (List Int)
maybeAngles angles =
    if all isAngle angles && sum angles < 180 then
        Just angles

    else
        Nothing


third : Int -> Int -> Maybe Int
third first second =
    maybeAngles [ first, second ]
        |> map (sum >> (-) 180)

Test it online

Here.

 

Keeping it simple in bash

function thirdAngle {
  echo $((180 - $1 - $2))
}

Running through the examples on the cmd:

> thirdAngle 30 60
90

> thirdAngle 60 60
60

> thirdAngle 43 78
59

> thirdAngle 10 20
150
 

BTW the challenge on Kata only tests for valid triangles,

function otherAngle(a, b) {
  return 180-(a+b);
}

was sufficient in JS

 

In Go!

func thirdAngle(a, b int) (int, error) {
    if (a + b) >= 180 {
        return 0, errors.New("Input angles sum is greater than or equal to 180 degress, this cannot be a triangle")
    }
    if a == 0 || b == 0 {
        return 0, errors.New("Input angle cannot be zero, cannot be a triangle")
    }
    angle := 360 - a - b // sum of angles must be 360 degress
    return angle, nil
}

Go Playground

 

This oughta do it for Elixir.

defmodule Triangle do
  def third_angle(a, b) when is_integer(a + b) # will not qualify if either isn't an integer
                         and a + b < 180 
                         and a > 0
                         and b > 0 do
    180 - a - b
  end
end
 
function thirdAngle(a,b) {
    return 180-a-b;
}
 
 

What happens if I enter thirdAngle(0,0)?

 

you are right, I just wrote it very fast and I did not think about this case.
TDD will help a lot in these situations.

Classic DEV Post from Jul 2 '19

Introducing Object.fromEntries

We're learning about ES2019 and this entry is all about understanding the Object.fromEntries function.

dev.to staff profile image
The hardworking team behind dev.to ❀️
DEV.join()

Come for the ideas.
Stay for the community.