Against time

Karan likes the number 4 very much. Impressed by the power of this number, Karan has begun to look for occurrences of four anywhere. He has a list of T integers, for each of them he wants to calculate the number of occurrences of the digit 4 in the decimal representation. He is too busy now, so please help him.

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In a company, an employee is paid as under. If his basic salary is less than Rs. 1500, then HRA = 10% of base salary and DA = 90% of basic salary.

If his salary is either equal to or above Rs. 1500, then HRA = Rs. 500 and DA = 98% of basic salary. If the Employee's salary is input, write a program to find his gross salary.
NOTE: Gross Salary = Basic Salary + HRA + DA

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Akhil has many balls of white and black colors. One day, he was playing with them. During the play, he arranged the balls into two rows both consisting of N number of balls. These two rows of balls are given to you in the form of strings X, Y. Both these strings consist of 'W' and 'B', where 'W' denotes a white-colored ball and 'B' is a black color ball.

Other than these two rows of balls, Akhil has an infinite supply of extra balls of each color. he wants to create another row of N balls, Z in such a way that the sum of Hamming distance between X and Z, and hamming distance between Y and Z is maximized.

Hamming Distance between two strings X and Y is defined as the number of positions where the color of balls in row X differs from the row Y ball at that position. e.g. Hamming distance between "WBB", "BWB" is 2, as, at positions 1 and 2, corresponding colors in the two strings differ.

As there can be multiple such arrangements of row Z, Akhil wants you to find the lexicographically smallest arrangement which will maximize the above value.

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Vishal loves running. He often visits his favorite Nehru Park and runs for very long distances. On one such visit, he found that the number of girls in the park was unusually high. Now he wants to use this as an opportunity to impress a large number of girls with his awesome speed.

The track on which he runs is an N kilometers long straight path. There are a_i girls standing within the ith kilometer of this path. A girl will be impressed only if Vishal is running at his maximum speed when he passes by her. But he can run at his best speed only for a single continuous stretch of K kilometers. Now Vishal wants to know what is the maximum number of girls that he can impress.

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Covid-19 is spreading fast! There are N cities, numbered from 0 To (N−1), arranged in a circular manner. City 0 is connected to city 1, 1 to 2, …, city (N−2) to city (N−1), and city (N−1) to city 0. The virus is currently in city X. Each day, it jumps from its current city to the city K to its right, i.e., from city X to the city (X+K)%N. As the virus jumps, the cities in-between don't get infected. Cities once infected stay infected. You live in city Y . Find if it will reach your city eventually. If it will, print YES, else print NO.

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