C program to remove duplicates from an ordered array

Write a ‘C’ program to remove duplicates from an ordered array. For example, if input array contains 10,10,10,30,40,40,50,80,80,100 then output should be 10,30,40,50,80,100.

Solution

#include <stdio.h>
int main()
{
    int arr[100]; 
    int size;     
    int i, j, k;  
    printf("Enter size of the array : ");
    scanf("%d", &size);
    printf("Enter elements in array : ");
    for(i=0; i<size; i++)
    {
        scanf("%d", &arr[i]);
    }
    for(i=0; i<size; i++)
    {
        for(j=i+1; j<size; j++)
        {
            if(arr[i] == arr[j])
            {
                for(k=j; k<size; k++)
                {
                    arr[k] = arr[k + 1];
                }
                size--;
                j--;
            }
        }
    }
    printf("\nArray elements after deleting duplicates : ");
    for(i=0; i<size; i++)
    {
        printf("%d\t", arr[i]);
    }
    return 0;
}

Output

Enter size of the array : 10

Enter elements in array : 3

4

5

6

5

3

7

8

2

Array elements after deleting duplicates : 3 4 5 6 7

8 2

Programming Examples

C program to remove duplicates from an ordered array