Maze

dfs and similar, dp, probabilities, trees

Spiders

dp, greedy, trees

Tree or not Tree

data structures, divide and conquer, implementation, trees

Party

dfs and similar, graphs, trees

Lucky Tree

dp, dsu, trees

Castle

dp, greedy, probabilities, sortings, trees

Help King

implementation, probabilities, trees

Leaders

dfs and similar, dsu, graphs, trees

Beautiful Road

dfs and similar, dp, dsu, graphs, implementation, sortings, trees

Genetic engineering

dp, string suffix structures, trees

Petya and Tree

binary search, dfs and similar, probabilities, sortings, trees

Pairs

dfs and similar, dp, dsu, graphs, implementation, trees

Beavermuncher-0xFF

dfs and similar, dp, dsu, greedy, trees

Gift

dsu, graphs, sortings, trees

Big Maximum Sum

data structures, dp, greedy, implementation, math, trees

Information Reform

dp, implementation, trees

Enemy is weak

data structures, trees

Eternal Victory

dfs and similar, graphs, greedy, shortest paths, trees

Caterpillar

dfs and similar, dp, graphs, trees

Galaxy Union

dp, trees, two pointers

Baldman and the military

dfs and similar, graphs, trees

Old Berland Language

data structures, greedy, trees

Ant on the Tree

constructive algorithms, dfs and similar, trees

Roads not only in Berland

dsu, graphs, trees

Scheme

dfs and similar, graphs, trees

Two Paths

dfs and similar, dp, graphs, shortest paths, trees, two pointers

Exposition

binary search, data structures, dsu, trees, two pointers