Scan Memory for Three Consecutive Increasing Values

Code

#include <stdio.h>

int find_pattern(int *mem, int n) {
    if (n <= 2) {
        return -1;
    }

    int* tmp = mem;
    int result = -1; // store result

    while (n > 2) {
        bool cmp_1st_pair = *tmp + 1 == *(tmp + 1);
        bool cmp_2nd_pair = *(tmp + 1) + 1 == *(tmp + 2);

        if (cmp_1st_pair && cmp_2nd_pair) {
            result = tmp - mem;
            break;
        };

        // skip one more step if no match on second pair
        int step = 1 + !cmp_2nd_pair;
        tmp += step;
        n -= step;
    }
    
    return result;
}

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;
}

Solving Approach