ID NAME QUALITY USERS ACC % DIFFICULTY C I
28451 Ada and Cities   4 60
12
17
28450 Ada and Path   5 55
17
30
17261 Bank robbery   2 183
17
23
10145 Birthday Cake   8 201
14
12
1693 Coconuts   8 599
22
29
3579 Disjoint Paths   2 287
23
34
4110 Fast Maximum Flow   31 1986
25
21
373 Greedy island   2 421
30
27
962 Intergalactic Map   4 506
22
29
4206 Fast Maximum Matching   16 1480
24
19
4485 MobiZone vs VinaGone   4 247
21
34
4227 "Shortest" pair of paths   3 174
23
17
3868 Total Flow   9 1225
12
13
287 Smart Network Administrator   3 387
24
31
203 Potholers   18 1828
17
14
22379 Mobile Company 2   1 52
12
17
4457 Shopping II   2 120
17
1
377 Taxi   11 1141
13
17

#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