Linear Search in Array

 Code

#include <stdio.h>
#include <stdint.h>

int linear_search(uint8_t *arr, uint8_t n, uint8_t key) {
    uint8_t found = 0; 

    for(int i = 0; i < n; i++){
        if(arr[i] == key){
            found = 1; 
            return i;
        }  
    }

    if(!found){
       return -1;
    }

}

int main() {
    uint8_t n, key;
    scanf("%hhu", &n);
    uint8_t arr[100];

    for (uint8_t i = 0; i < n; i++) {
        scanf("%hhu", &arr[i]);
    }
    scanf("%hhu", &key);

    int index = linear_search(arr, n, key);
    printf("%d", index);
    return 0;
}

Solving Approach

Iterate through the array until an element matches the key, if match is found return the index, and set the flag "found" to 1 if not match is found flag 'found' won't change therefore returns -1;