ID NAME QUALITY USERS ACC % DIFFICULTY C I
18164 Atoms in the Lab   28 3291
7
5
328 Bishops   76 7798
14
6
2009 Cryptography   1 79
1
34
314 Digits of e   3 2856
1
1
24 Small factorials   138 35088
15
9
6236 Matches   7 426
27
8
36563 Hard Fibonacci   7 46
20
20
2906 GCD2   49 5776
12
10
2901 One Geometry Problem   9 1579
4
13
10676 0110SS   24 1629
13
9
54 Julka   149 17395
19
6
5699 The last digit re-visited   36 6980
9
9
3932 Point Connection Game in a Circle   2 686
12
17
3970 Convert to Decimal Base System   50
17
17
16034 Minimum Number   4 478
11
1
3023 Binary multiplication   3 224
17
17
35954 New Data Type   96
6
6
18905 Kapti and Balu   1 34
17
17
8676 Digits of Phi (Golden Ratio)   1 286
17
17
270 Digits of Pi   10 5618
9
16
5294 Recurrence   2 248
28
17
29748 Robin Hood   25
1
1
3362 Setnja   2 229
9
17
10334 SOLDIERS   5 632
11
4
1423 Digits of SQRT(2)   5 2645
13
13
738 Another Counting Problem   217
71 Tree   2 402
12
9
1002 Uncle Jack   11 2834
9
8
235 Very Fast Multiplication   21 942
26
22
6479 The Very Greatest Common Divisor   3 85
23
12
1475 Play with Digit Seven   4 82
30
13

#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