Codeforces Beta Round 84 (Div. 2 Only)

2 problems from Codeforces Beta Round 84 (Div. 2 Only) (contest 110), difficulty 800-1100. 2/2 solutions verified against sample I/O.

2 items

Codeforces Beta Round 84 (Div. 2 Only)

Div. 2 | 2 problems | 2/2 verified | Difficulty 800-1100 | 5m 34s

#	Problem	Rating	Tags	Accepted	Time	✓
A	Nearly Lucky Number	800	implementation	199,391	2m 36s	✓
B	Lucky String	1100	constructive-algorithms, strings	11,019	2m 58s	✓

Practice › Codeforces Solutions › Codeforces Beta Round 84 (Div. 2 Only) ›

CF 110A - Nearly Lucky Number

We are given a positive integer and need to decide whether it is a nearly lucky number. A number is considered nearly lucky if the count of its lucky digits-digits equal to 4 or 7-is itself a lucky number. A lucky number contains only 4s and 7s in its decimal representation.

Practice › Codeforces Solutions › Codeforces Beta Round 84 (Div. 2 Only) ›

CF 110B - Lucky String

We need to build a lowercase string of length n that satisfies a special condition on repeated letters. For every character, we look at all positions where it appears.