#include <stdio.h> #include <stdint.h> int binary_search(uint8_t *arr, uint8_t n, uint8_t key) { uint8_t start=0,end=n-1; while(start<=end){ if(arr[start]==key) return start; else if(arr[end]==key) return end; start++,end--; } 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 = binary_search(arr, n, key); printf("%d", index); return 0; }
Test Cases
Test Results
Input
6 5 10 15 20 25 30 20
Expected Output
3