﻿ C : Find the number of times a number occurs in an array

# C Exercises: Find the number of times occurs a given number in an array

## C Array: Exercise-53 with Solution

Write a program in C to find the number of times a given number appears in an array.

Visual Presentation:

Sample Solution:

C Code:

``````#include <stdio.h>

// Function for binary search to find the first or last occurrence of a given element
int BinSearch(int arr1[], int n, int x, int searchFirst) {
int low = 0, high = n - 1;
int result = -1;
while (low <= high) {
int mid = (low + high) / 2;
if (x == arr1[mid]) {
result = mid;
// Search for first occurrence of x
if (searchFirst)
high = mid - 1;
else // Search for last occurrence of x
low = mid + 1;
} else if (x < arr1[mid])
high = mid - 1;
else
low = mid + 1;
}
return result;
}

int main(void) {
int arr1[] = {2, 3, 4, 4, 4, 4, 5, 5, 5, 6, 7, 7};
int srch_num = 4; // Element to search
int n = sizeof(arr1) / sizeof(arr1[0]);
int i;
//------------- print original array ------------------
printf("The given array is: ");
for (i = 0; i < n; i++) {
printf("%d ", arr1[i]);
}
printf("\n");
//------------------------------------------------------

// Find the first and last occurrences of srch_num in the array
int first = BinSearch(arr1, n, srch_num, 1);
int last = BinSearch(arr1, n, srch_num, 0);
int ctr = last - first + 1; // Calculate the count of occurrences

if (first != -1)
printf("The number of times the number %d occurs in the given array is: %d", srch_num, ctr);
else
printf("No such element found in the array.");

return 0;
}
```
```

Sample Output:

```The given array is :  2  3  4  4  4  4  5  5  5  6  7  7
The number of times the number 4 occurs in the given array is:  4
```

Flowchart:

C Programming Code Editor:

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