Alice and the Chessboard It's Sunday afternoon, and Alice is in her room trying to figure out the rules of the game called Ch... |

Alice vs. Bob We have found an Idea to end the everlasting rivalry between Alice and Bob. We will give them a list...
Moderate
12/23/65 |

An Act of Uniformly Random Kindness After selling all the bitcoins that you bought back in 2010, you now find yourself with a huge amoun... |

Combination Lock Imagine a Combination Lock - If you set the numbers to a preset combination (passcode), the lock wi... |

Diagonal Sum Given an N×N size matrix, you have to re-arrange the elements of the matrix in such a way that the d... |

Find Prime A prime number is a positive integer that is divisible only by itself and 1. The first few prime num... |

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... |

K-th DuoPalindrome Alice likes playing with Palindromes (strings that read the same backward as forward, such as 'madam... |

Meena and Random Choice Meena has an array of length N (1-indexed). The numbers of the array are arranged from left to right...
Moderate
6/6/8 |

Mischievous Meme Maker Memes are love, memes are life. Living in 2018, we are all very familiar with internet memes. They a...
Moderate
76/96/154 |

Smallest Interval Alice has a collection of N numbers. She would like to place them on a number line. She places each ... |

The Game Is Back On Moriarty is bored again. When he gets bored, the only thing he wants to do is play with Sherlock. So... |

XOR and the Array Given an array of N integers, you need to find out the minimum number of integers that must be added... |

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