ID NAME QUALITY USERS ACC % DIFFICULTY C I
18164 Atoms in the Lab   23 2988
7
4
328 Bishops   65 7349
14
6
2009 Cryptography   76
314 Digits of e   1 2775
1
1
24 Small factorials   105 31335
15
9
6236 Matches   5 416
28
6
2906 GCD2   42 5381
11
10
2901 One Geometry Problem   8 1527
5
13
10676 0110SS   17 1542
12
6
54 Julka   119 15959
19
6
5699 The last digit re-visited   32 6682
9
9
3932 Point Connection Game in a Circle   1 662
12
17
3970 Convert to Decimal Base System   48
17
17
16034 Minimum Number   3 444
13
1
3023 Binary multiplication   2 219
17
17
18905 Kapti and Balu   1 31
17
17
8676 Digits of Phi (Golden Ratio)   1 285
17
17
270 Digits of Pi   7 5453
10
17
5294 Recurrence   1 241
34
17
29748 Robin Hood   24
1
1
3362 Setnja   221
10334 SOLDIERS   5 607
11
4
1423 Digits of SQRT(2)   3 2577
12
6
738 Another Counting Problem   217
71 Tree   2 394
12
9
1002 Uncle Jack   9 2766
9
8
235 Very Fast Multiplication   16 807
28
22
6479 The Very Greatest Common Divisor   2 75
26
9
1475 Play with Digit Seven   3 67
17
17

#big-numbers

The problem involves arbitrary precision arithmetic

https://en.wikipedia.org/wiki/Arbitrary-precision_arithmetic https://en.wikipedia.org/wiki/Karatsuba_algorithm - efficient multiplication algorithm https://en.wikipedia.org/wiki/Toom%E2%80%93Cook_multiplication - as above https://en.wikipedia.org/wiki/Sch%C3%B6nhage%E2%80%93Strassen_algorithm - as above https://en.wikipedia.org/wiki/F%C3%BCrer%27s_algorithm - as above