lets say we have two positive number a,b and without loss of generality lets a>b , let dif:=a-b. dif is also a positive number(since a>b). but dif<a because some positive number is substracted from a. but our solution demands the case that dif>=a and dif>=b.

Use hashed data structure when you are sure that key is not randomized , if it is consecutive then feel free to use it.
Ex:- reverse mapping an array to its index when array is permutation. Never use this when array can be randomly any number because test case can be made so make lots of collisions.

If you are doing competitive coding don't rely on pow function because it is not intended for integer .

The actual formulation that c++ uses is :

a^b=e^(b*log(a)).
This type of floating point calculation is error prone, and is recommended never to use. Built your own code of logarithmic time multiplication or directly copy from internet like gfg.
Some C++'s function on which you can rely (at least I had experience no error ) is:
- sqrt
- log10,log2,log10

as the name suggest it is basic But you are Pro So don't loose your dignity.

sometimes unexpected bruteforce works . Today it worked for problem C for me

Every intellectual having more than one year experience of coding when solves first and only problem of div2 thinks that becoming tourist is not hard,
An intellectual,2021

say along with me , "Hail monoGon"

Is april a fool day . Is 1st april a fool month. Is this day maker a fool. Was celebrater a fool. Or we are fools?

The worst fool I am in the whole world . Today I came to know? and By the way miss You , you fKing foolish day.

11 6 7 10 9 9 8 ,can anybody explain why and how it is yes

codechef needs to provide some more test cases so that when we build our solution , we could be sure that we have interpreted the problem in the way they said. because If we know the solution and get penalities free of cost due to misinterpretation is too bad. One of the reason I don't like cookoff. The minimum insertion was too confusing and required mathematical reasoning to understand the problem. If they would have given sufficient test case we can be assured that what we are doing is right or wrong.

I saw that was awsome. More specifically the problem D. Where I learnt Nobody is perfect . It shows he is also a Human Not a computer(I mean a program which makes program);