Question

C Programming Language

Problem Title: Discount

Jojo is browsing the internet while suddenly he sees an ad about the new cafe. The promotion is if the price of an item is N dollars, then you can buy the second item for half the price, the third item for a quarter of the original price, and so on, but if it becomes less than M dollars, then you have to pay M dollars. He wonders how much he has to pay if he buys K item

Format Input

The first line will contain an integer T, the number of test cases. Each test case will have 3 integers N, M, and K, each denoting the original price, the minimum price, and the amount Jojo is going to buy.

Format Output

For each test case, print “Case #X: “ (X starts with 1), then followed by the price Jojo has to pay rounded to 3
decimal digits.
.

Constraints

• 1 ≤ T ≤ 10
• 1 ≤ M ≤ N ≤ 1000000000
• 1 ≤ K ≤ 1000000000

Sample Input & Output (standard input & output)

3

10 5 3

Case #1: 20.000

100 5 3

Case #2: 175.000

100 100 4

Case #3: 400.000

Explanation

In the first case, the original price is 10 dollars, the price for the second item is 5 dollars, the price for the third item is 5 dollars too because 2.5 is less than 5. In the third case, all item won’t be lower than the original price.

Answer 1

Discount problem CODE(in C):

#include <stdio.h>

int main(void) {

int T;

long long M,N,K; //declaring our variables

double price; //Declaring a price variable

scanf("%d", &T); //Promting the user to enter the number of test cases (T)

for(int i=1; i <= T; i++){

price = 0;

scanf("%lld %lld %lld", &N, &M, &K); //Prompting the user to input the values

double A = N; //Taking a duplicate of the original price as double variable

while (K > 0){

if (A < M){ //If the price is less than M

price = price + M; //Incrementing price with M dollars

K = K - 1;

continue;

}

price = price + A; //else incrementing price with A

A = A/2; //Updating A (i.e., Making the original price half for every iteration)

K = K - 1 ;

// printf("%f %f\n",sum,A);

}

printf("Case #%d: %.3f\n",i,price);//Printing on the output screen

}

return 0;

}

CODE IMPLEMENTATION:

TESTING OUR CODE (OUTPUT 1):

TESTING OUR CODE(OUTPUT 2):

NOTE:

# We must declare N,M,K as long long integers because, the given constraints for those variables are very large.

# Any questions or clarifications regarding this question can be asked in the comments section.