Interesting Parenthesis Parentheses sequence of length 2n is the sequence containing exactly n opening parentheses «(» and e... |
Oishi Teacher and Her Naughty Class Oishi teacher has returned to her class after the tiffin break. She noticed that some students who r... |
Is Bita Happy? Bita has learned bitwise-operations recently. She is doing some experiments with these operations no... |
Happy Sub-Sequence Recently Alex has participated in a programming contest. He became 1st runner up. He couldn't solve ... |
Snake's Neck Remember Violet and Dash from the movie "The Incredibles"? The two siblings recently installed the c... |
Is This a Give-Away? Once there lived an ancient mage named Farabi. He could always give perfect weather forecast. He nev... |
K-Game To end the everlasting rivalry between Tom and Jerry, the Lady of the house found an Idea. She gives... |
Generation Gap There are n people standing in a queue. The age of the ith person is ai. The more the age gap betwee... |
Lucky Stone Game Alice and Bob are playing a stone game. They consider 4 and 7 as lucky numbers and they like to make... |
Lexicographical Smallest String There is a string $s$ of length $n$ containing lowercase letters and an integer $k$. Among the lette... |
Smart Feature Phone 2 Alice worked in CIA. Right now he need to send an encrypted message to the headquarter(HQ) of CIA. ... |
m-Beautiful Numbers An m-Beautiful Number is a number which is divisible by $m$ and the sum of the digits is also divisi... |
Lets Play Pipeline In this problem you will have to solve a puzzle game named "Pipeline". 90's kids knows this game ver... |
COVID-19 Outbreak COVID-19 outbreak in Atlantis is so bad that the government is forced to lock down the whole country... |
Polygon Construction (Hard) Meera in going to picnic with her friends. They are going to have lots of fun. They will be doing va... |
Harry Potter and the Vault of Gringotts "There was a break-in of Gringotts Wizarding Bank on 1 May, 1998, during the height of the Second Wi... |
No GCD You are given N integers. Each integer is square free (i.e. it has no divisor which is a square numb... |
XOR Is Fun Efa hates numbers. But she loves the XOR operation. This time, you have to solve another problem for... |
Super Mario Bros Every kid loves to play Super Mario Bros. Mario moveু forward and collects coins in a stage. Stages ... |
Without Any Legend You have two arrays $A_1, A_2, ..., A_N$ and $C_1, C_2, ..., C_N$ of length $N$. Initially for each ... |
Holy Tree What is a tree? A tree is a bidirectional connected graph with no cycle. In a tree, we can create ... |
Very Dirty String Strings are difficult, most of the contest programmers say this and try to avoid string algorithms. ... |
MSIS! Do you know what MSIS is? MSIS is the abbreviation for Maximum Sum Increasing Subsequence. It is a s... |
My Small Number You are given two integers N and M. Find another integer X divisible by M that has the same number o... |
Third Dimension Mr. J wants to learn about combinatorics. He started reading a book on combinatorics and came across... |