Sum or Product

Contributed by

Ankush Gupta

Easy

Avg time to solve 15 mins

Success Rate 80 %

1245 upvotes

Problem Statement

You are given a number ‘N’ and a query ‘Q.’ If ‘Q’ is 1, then you have to return the sum of all integers from 1 to ‘N,’ else if ‘Q’ is equal to 2 then you have to return the product of all integers from 1 to ‘N.’ Since the product can be very large, return it modulo 10 ^ 9 + 7.

For example

Given ‘N’ = 4, ‘Q’ = 1. 
Then the answer is 10 because the sum of all integers between 1 and 4 are 1, 2, 3, and 4. Hence 1 + 2 + 3 + 4 is equal to 10.

Detailed explanation ( Input/output format, Notes, Constraints, Images )

Input format:

The first line of input contains an integer ‘T’ denoting the number of test cases.

Next, ‘T’ lines contain two space-separated integers ‘N’, where ‘N’ is the number given and ‘Q’, denoting the type of query.

Output Format :

For each test case, You are supposed to return an integer denoting the sum or product of ‘N’ numbers.

Note:

You are not required to print the expected output; it has already been taken care of. Just implement the function.

Constraints:

1 <= ‘T’ <= 10
1 <= ‘N’ <= 10^4
1 <= ‘Q’ <= 2

Time Limit: 1 sec.

Sample Input 1 :

2
4 1 
4 2

Sample Output 1 :

10
24

Explanation of the Sample Input 1:

In the first test case, the answer is 10 because all integers between 1 and 4 are 1, 2, 3, and 4. Hence 1 + 2 + 3 + 4 is equal to 10.


In the second test case, the answer is 25 because all integers between 1 and 4 are 1, 2, 3, and 4. Hence 1 * 2 * 3 * 4 is equal to 24.

Sample Input 2 :

2
5 1
5 2

Sample Output 2 :

15
120

Console