122 A - Lucky Division| Codeforces Lucky Division Solution| A2oj Ladders Div 2A.

Petya considers the numbers which have 4 and 7 as lucky numbers. Considering all the permutations we get 12 different numbers. These are the 12 different permutations of numbers.Text 4,7,47,74,44,444,447,474,477,777,774,744 Petya also considers it al...