ID NAME QUALITY USERS ACC % DIFFICULTY C I
28451 Ada and Cities   9 114
19
17
28450 Ada and Path   7 78
15
28
17261 Bank robbery   2 231
17
23
10145 Birthday Cake   7 233
12
12
1693 Coconuts   12 686
21
28
3579 Disjoint Paths   4 307
24
27
4110 Fast Maximum Flow   42 2426
25
21
373 Greedy island   5 480
26
26
962 Intergalactic Map   3 534
19
28
4206 Fast Maximum Matching   29 1792
23
20
4485 MobiZone vs VinaGone   7 298
17
31
4227 "Shortest" pair of paths   3 180
23
17
3868 Total Flow   12 1301
14
12
287 Smart Network Administrator   3 400
24
31
203 Potholers   22 2102
16
12
22379 Mobile Company 2   2 64
13
17
4457 Shopping II   3 132
17
1
377 Taxi   14 1205
13
16

#max-flow

The problem involves maximum flow problem

https://en.wikipedia.org/wiki/Maximum_flow_problem http://www.cs.princeton.edu/courses/archive/spr04/cos226/lectures/maxflow.4up.pdf