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C Exercises: Remove the duplicates from a given array of integers

C Programming Practice: Exercise-12 with Solution

Write a C programming to remove the duplicates from a given array of integers.

C Code:

#include <stdio.h>
#include <stdlib.h>
static int remove_duplicates(int* nums, int arr_size)
{
    if (arr_size <= 1) {
        return arr_size;
    }

    int i = 0, j, count = 1;
    while (i < arr_size) {
        for (j = i + 1; j < arr_size && nums[i] == nums[j]; j++) {}
        if (j < arr_size) {
            nums[count++] = nums[j];
        }
        i = j;
    }

    return count;
}

int main(void)
{
    int nums[] = {1,1,2,3,4,4,5,6,6,6};    
    int size = sizeof(nums)/sizeof(nums[0]);
    printf("Original array:\n");
    int i;
    for (i = 0; i < size; i++) {
        printf("%d ", nums[i]);
    }
    int count = remove_duplicates(nums, size);
    printf("\nAfter removing duplicates from the above sorted array:\n");
    for (i = 0; i < count; i++) {
        printf("%d ", nums[i]);
    }
    printf("\n");
    return 0;
}

Sample Output:

Original array:
1 1 2 3 4 4 5 6 6 6 
After removing duplicates from the above sorted array:
1 2 3 4 5 6 

Pictorial Presentation:

C Programming: Remove the duplicates from a given array of integers.

Flowchart:

C Programming Flowchart: remove the duplicates from a given array of integers.

C Programming Code Editor:

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Previous: Write a C programming to generate all combinations of well-formed parentheses from n given pairs of parentheses.
Next: Write a C program to remove all instances of a given value in a given array of integers and return the length of the new array.

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C Programming: Tips of the Day

The tilde operator in C:

The ~ operator is bitwise NOT, it inverts the bits in a binary number:

NOT 011100
  = 100011

Ref : https://bit.ly/3DR1N24