Overview

Usually I try to solve the original challenge from Project Euler first and then tackle its modified version at Hackerrank which is often harder.

Heatmap

green problems solve the original Project Euler problem and have a perfect score of 100% at Hackerrank, too.
yellow problems score less than 100% at Hackerrank (but still solve the original problem).
gray problems are already solved but I haven't published my solution yet.
blue problems are already solved and there wasn't a Hackerrank version of it (at the time I solved it) or I didn't care about it because it differed too much.

Please click on a problem's number to open my solution to that problem:

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75
76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100
101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125
126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150
151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175
176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200
The 133 solved problems had an average difficulty of 16.9% at Project Euler and I scored 11,174 points (out of 12300) at Hackerrank's Project Euler+.

Most recently solved

May 24, 2017: Problem 134 - Prime pair connection
May 23, 2017: Problem 187 - Semiprimes
May 23, 2017: Problem 174 - Counting the number of "hollow" square laminae that can form one, two, three, ... distinct arrangements
May 23, 2017: Problem 151 - Paper sheets of standard sizes: an expected-value problem
May 23, 2017: Problem 101 - Optimum polynomial
May 22, 2017: Problem 173 - Using up to one million tiles how many different "hollow" square laminae can be formed?
May 21, 2017: Problem 129 - Repunit divisibility
May 19, 2017: Problem 136 - Singleton differences
May 19, 2017: Problem 135 - Same differences
May 19, 2017: Problem 124 - Ordered radicals
  ... and 120 more ...

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