Hackerrank HourRank round 5 difficult question, incomplete

hack.cpp

#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>

using namespace std;
const int N = 100005;

int n, q; long long k;
char s[N]; int pos[N], sa[N], tmp[N], lcp[N], gap;

inline bool cmp(int i, int j) {
    if (pos[i] != pos[j]) return pos[i] < pos[j];
    i += gap, j += gap;
    return i < n && j < n ? pos[i] < pos[j] : i > j;
}

void build() {
    s[n++] = '$';
    for (int i = 0; i < n; ++i) {
        sa[i] = i;
        pos[i] = s[i];
    }
    for (gap = 1;; gap <<= 1) {
        sort(sa, sa + n, cmp);
        for (int i = 1; i < n; ++i)
            tmp[i] = tmp[i - 1] + cmp(sa[i - 1], sa[i]);
        for (int i = 0; i < n; ++i)
            pos[sa[i]] = tmp[i];
        if (tmp[n - 1] == n - 1)
            break;
    }
    for (int i = 0, k = 0; i < n; ++i) {
        if (pos[i] + 1 < n) {
            for (int j = sa[pos[i] + 1]; s[i + k] == s[j + k]; ++k);
            lcp[pos[i]] = k;
            if (k) --k;
        } else {
            lcp[pos[i]] = 0;
        }
    }
    for (int i = 1; i < n; ++i) {
        if (lcp[i])
    }
}

int main() {
    scanf("%d%d", &n, &q);
    scanf("%s", s);
    build();
    while (q--) {
        scanf("%lld", &k);
    }
    
}