OI-codes/S2OJ/164/data/std.cpp

#include <bits/stdc++.h>
using namespace std;

inline int read() {
    int x = 0, f = 1, c = getchar();
    while (c < 48) c == '-' && (f = -1), c = getchar();
    while (c > 47) x = x * 10 + c - '0', c = getchar();
    return x * f;
}

const int MAXN = 200005;
int ls[MAXN * 32], rs[MAXN * 32], sum[MAXN * 32];
int rt[MAXN], val[MAXN], raw[MAXN];
int n, m, q, tot;

void insert(int &x, int y, int l, int r, int k) {
    ls[x = ++tot] = ls[y];
    rs[x] = rs[y];
    sum[x] = sum[y] + 1;
    if (l == r) return;
    int mid = (l + r) >> 1;
    if (k <= mid) insert(ls[x], ls[y], l, mid, k);
    if (k > mid) insert(rs[x], rs[y], mid + 1, r, k);
}

int query(int x, int y, int l, int r, int k) {
    if (l == r) return l;
    int mid = (l + r) >> 1, s = sum[ls[y]] - sum[ls[x]];
    if (k <= s) return query(ls[x], ls[y], l, mid, k);
    return query(rs[x], rs[y], mid + 1, r, k - s);
}

int main(int argc, char const *argv[]) {
    n = read();
    q = read();
    for (int i = 1; i <= n; ++i)
        val[i] = raw[i] = read();
    sort(val + 1, val + n + 1);
    m = unique(val + 1, val + n + 1) - val - 1;
    for (int i = 1, k; i <= n; ++i) {
        k = lower_bound(val + 1, val + m + 1, raw[i]) - val;
        insert(rt[i], rt[i - 1], 1, m, k);
    }
    for (int i = 1, l, r, k, x; i <= q; ++i) {
        l = read();
        r = read();
        k = read();
        x = query(rt[l - 1], rt[r], 1, m, k);
        printf("%d\n", val[x]);
    }
    return 0;
}