#include <stdio.h> int find_pattern(int *mem, int n) { int *ptr = mem; int *start = mem; int count = 1; ptr++; while(ptr < mem + n - 2) { if(*ptr == *start + count) { if(ptr == start + 2) return start - mem; count++; } else { start++; count = 1; } ptr++; } return -1; } int main() { int n, arr[100]; scanf("%d", &n); for (int i = 0; i < n; i++) { scanf("%d", &arr[i]); } int res = find_pattern(arr, n); printf("%d", res); return 0; }
Test Cases
Test Results
Input
8 2 4 5 6 9 11 12 14
Expected Output
1