Unknown Language Round 1

9 problems from Unknown Language Round 1 (contest 64), difficulty 1300-2400. 9/9 solutions verified against sample I/O.

9 items

Unknown Language Round 1

Special | 9 problems | 9/9 verified | Difficulty 1300-2400 | 14m 26s

# Problem Rating Tags Accepted Time ✓
A Factorial 1300 *special, implementation 4,247 1m 13s ✓
B Expression 1500 *special, expression-parsing 1,053 1m 39s ✓
C Table 1600 *special, greedy, implementation 356 1m 25s ✓
D Presents 1800 *special, greedy 298 1m 40s ✓
E Prime Segment 1800 *special, brute-force, math 295 1m 28s ✓
F Domain 2000 *special, expression-parsing 193 1m 37s ✓
G Path Canonization 2200 *special 129 1m 42s ✓
H Table Bowling 2300 *special, sortings 122 1m 52s ✓
I Sort the Table 2400 *special, sortings 94 1m 50s ✓
Practice › Codeforces Solutions › Unknown Language Round 1 ›

CF 64A - Factorial

We are asked to compute the factorial of a given integer $n$. Factorial is the product of all positive integers up to $n$, so for $n = 3$, the factorial is $1 times 2 times 3 = 6$. The input is a single integer, and the output is the single integer result of this product.
codeforces competitive-programming *special implementation May 28, 2026
Practice › Codeforces Solutions › Unknown Language Round 1 ›

CF 64B - Expression

The input is a tiny arithmetic expression written as a three-character string. The first and third characters are digits from 0 to 9, and the middle character is either + or -. The task is to evaluate the expression and print the resulting integer.
codeforces competitive-programming *special expression-parsing May 28, 2026
Practice › Codeforces Solutions › Unknown Language Round 1 ›

CF 64C - Table

We are given an $n times m$ table filled with consecutive integers starting from 1. The filling is done row by row, left to right.
codeforces competitive-programming *special greedy implementation math May 28, 2026
Practice › Codeforces Solutions › Unknown Language Round 1 ›

CF 64D - Presents

We are given three positive integers representing the prices of three presents. There are three sisters, ranked by age: eldest, middle, and youngest.
codeforces competitive-programming *special greedy May 28, 2026
Practice › Codeforces Solutions › Unknown Language Round 1 ›

CF 64E - Prime Segment

We are asked to find the closest prime numbers surrounding a given integer n. Concretely, we need two numbers, a and b, such that a ≤ n ≤ b and both a and b are prime. Among all prime intervals containing n, the one with the smallest length b - a is preferred.
codeforces competitive-programming *special brute-force math number-theory May 28, 2026
Practice › Codeforces Solutions › Unknown Language Round 1 ›

CF 64F - Domain

We need to decide whether a given string can be interpreted as a valid domain name under a simplified set of rules. The string may only contain lowercase English letters, digits, and dots. Dots separate the string into segments.
codeforces competitive-programming *special expression-parsing May 28, 2026
Practice › Codeforces Solutions › Unknown Language Round 1 ›

CF 64G - Path Canonization

We are given an absolute Unix-style path. The path is split into components by /, and every component represents either a normal directory or file name, ".", or "..". A normal name means “go into this directory or file”. The component ".
codeforces competitive-programming *special May 28, 2026
Practice › Codeforces Solutions › Unknown Language Round 1 ›

CF 64H - Table Bowling

We are given the final standings of a table bowling tournament. Every participant has a unique name and an integer score. The task is not just to sort the players, but also to assign ranking labels in the style used in real tournaments.
codeforces competitive-programming *special sortings May 28, 2026
Practice › Codeforces Solutions › Unknown Language Round 1 ›

CF 64I - Sort the Table

We are given a table where every row contains several string fields, and the first input line tells us the name of each column. Another line describes how the rows should be ordered. Each rule has the form COLUMNNAME ASC or COLUMNNAME DESC.
codeforces competitive-programming *special sortings May 28, 2026