Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
Sum of series with alternate signed squares of AP
An arithmetic progression (AP) is a series of numbers in which the difference between two consecutive terms in the same. The difference is calculated by subtracting the second term from the first.
Let's take a sample sequence to know about AP,
5, 7, 9, 11, 13, 15, . . . The common difference(d) of this arithmetic progression is 2. This means every succeeding element differs the former one by 2. The first term (a) of this series is 5.
The general formula for finding the nth term is a{n} = a + (n-1)(d)
In this problem, we are given an AP and we need to find the sum of series with alternate signed square, the series will look like,
a12 - a22 + a32 - a42 + a52 +......
Let's take an example, to make this more clear −
Input: n = 2 Output: -10
Explanation
12 - 22 + 32 - 42 = -10
Example
#include <stdio.h>
int main() {
int n = 4;
int a[] = { 1, 2, 3, 4, 5, 6, 7, 8}; int res = 0;
for (int i = 0; i < 2 * n; i++) {
if (i % 2 == 0) res += a[i] * a[i]; else res -= a[i] * a[i];
}
printf("The sum of series is %d", res);
return 0;
}Output
The sum of series is -36
Updated on: 19-Aug-2019
174 Views
Advertisements