Unofficial Editorial of problem CHEFEXQ from codechef december 2017 long contest

Problem link: CHEFEXQ Given an array of n elements and q queries of 2 types: type 1: Given two numbers p and x, the value at index p should be updated to x. type 2: Given two numbers p and x, calculate total number of subarrays whose starting index is 0 and the last index is ≤ p and the xor of all elements in that...

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[Tutorial] Snake Eating Problem of Codechef Snackdown 2017 Qualification round

Abridged problem description: Given the length of $n$ snakes, $a_0, a_1, a_2, ......... a_{n-1}$. A snake $i$ can eat another snake $j$, if $a_j \leq a_i$ and after eating a snake, it's length is increased by 1. Given $q$ queries. Each query contains an integer $x$, you have to tell what is the maximum number of snakes you can get which are of length at least $x$. Problem link: SNAKEEAT Soultion:  Let...

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