C PROGRAMMING PROGRAM • ARRAYS, SEARCHING & SORTING

Rotate an Array Right by One Position

Learn how to rotate an array right by one position using a clear C program.

BeginnerArraysRotationShift

PROBLEM UNDERSTANDING

Input and expected output

Sample input
5
1 2 3 4 5
Sample output
5 1 2 3 4

COMPLETE C PROGRAM

Complete C implementation

rotate-array-right-once.c
Open in compiler
#include <stdio.h>

int main(void)
{
    int size, values[100];

    printf("Enter array size: ");
    scanf("%d", &size);
    if (size < 1 || size > 100) return 1;
    for (int index = 0; index < size; index++) scanf("%d", &values[index]);
    int last = values[size - 1];
    for (int index = size - 1; index > 0; index--) values[index] = values[index - 1];
    values[0] = last;
    for (int index = 0; index < size; index++) printf("%d%c", values[index], index == size - 1 ? '\n' : ' ');
    return 0;
}

GUIDED CODE TOUR • NOT LIVE EXECUTION

Study the program line by line

Use the real compiler button above to run and debug with different inputs.

CURRENT STEP

Select Start to walk through the important lines.

SELECTED LINE

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EXPECTED OUTPUT FOR THE SAMPLE

5 1 2 3 4
0%Step 0 of 0

PROGRAM EXPLANATION

Algorithm and explanation

  1. Read the required input values.
  2. Save the last element, shift the others right and place the saved value first.
  3. Display the computed result.

Save the last element, shift the others right and place the saved value first.

EFFICIENCY

Time and space complexity

Time complexity

O(n)

Auxiliary space

O(n)

DEBUGGING CHECKLIST

Common mistakes

Check this

Use the correct format specifier for every variable.

Check this

Initialize variables before using their values.

Check this

Check braces, semicolons and input order carefully.

Try it yourself

Practice: Run the program with the sample input, predict its output, and then test one boundary case of your own.