Count Repeated Elements in an Array in C Programming

Count Repeated Elements in an Array is generally ask in interviews.

This problem can be solved in any language.

Here we will discuss algorithm to count repeated elements and implement it on C programming.

Count Repeated Elements in an Array in C Programming
Fig: Count Repeated Elements in an Array in C Programming

What is Repeated Elements

Repeated elements are elements that occurs more than one time in a list or in a sequence.

Consider following list

1 2 3 4 5 6 7 7 2 3 3 3

Here element 2 is repeating 2 times 3 is repeating 4 times and 7 is repeating 2 times.

This thing we have to implement in programming.

So our input is list or sequence on elements.

and output is repeated elements and repetition number.

So how we will turn our input to output?

Algorithm to Count Repeated Elements

Lets define our Algorithm that will get input and give use desired output.

  1. Create Array arr[] and repeated[][]
  2. Take input from user and store to arr
  3. For each element of arr check is it in repeated array or not
  4. If element found then increase element count
  5. Else add element to repeated array
  6. Print repeated array that has count 2 or more

Above is our simple step to develop our program

Program to Count Repeated Elements in C Programming

Based on above algorithm we develop this program.

Result

Hope you learn from this example