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2 years ago
#include <algorithm>
#include <cstdio>
#include <cmath>
#include <cstring>
using namespace std;
//快读
int read() {
int x = 0, f = 1;
char ch = getchar();
while (ch < '0' || ch > '9') {
if (ch == '-') f = -1;
ch = getchar();
}
while (ch >= '0' && ch <= '9') {
x = (x << 3) + (x << 1) + (ch ^ 48);
ch = getchar();
}
return x * f;
}
const int N = 400010;
int n, m;
int a[N]; //维护的序列
int ans[N]; // 结果
struct Node {
// op=1 插入, op=-1 删除, op=2 查询
int op;
// 插入l:插入的值,用于二分与mid PK,r:位置
// 删除l:删除的值,用于二分与mid PK,r:位置
// 查询 [l,r]:查询范围
// k:第k小
int l, r, k;
int id;
} q[N], lq[N], rq[N];
//树状数组
int tr[N];
void add(int x, int c) {
for (; x < N; x += x & -x) tr[x] += c;
}
//查询x的个数和
int getSum(int x) {
int sum = 0;
for (; x; x -= x & -x) sum += tr[x];
return sum;
}
void solve(int l, int r, int ql, int qr) {
if (ql > qr) return; //防止RE递归边界
if (l == r) { //递归到叶子结点,找到答案
for (int i = ql; i <= qr; i++)
if (q[i].op == 2) ans[q[i].id] = l; //所有查询请求,标识答案
return;
}
int mid = (l + r) >> 1;
int nl = 0, nr = 0;
for (int i = ql; i <= qr; i++) {
if (q[i].op < 2) {
//插入、删除操作二分
if (q[i].l <= mid)
add(q[i].r, q[i].op), lq[++nl] = q[i]; //根据q[i].op的不同通过一样的add函数在位置q[i].r处完成插入+1删除-1的操作
else
rq[++nr] = q[i];
} else {
//查询数组二分
int t = getSum(q[i].r) - getSum(q[i].l - 1);
if (q[i].k <= t)
lq[++nl] = q[i];
else {
q[i].k -= t;
rq[++nr] = q[i];
}
}
}
// 有借有还,再借不难
for (int i = ql; i <= qr; i++)
if (q[i].op < 2)
if (q[i].l <= mid) add(q[i].r, -q[i].op);
for (int i = 1; i <= nl; i++) q[ql - 1 + i] = lq[i]; //将左儿子操作数组拷贝到q中原来的下标是[0~ql-1],现在无缝接上[ql-1+1~ql-1+nl]
for (int i = 1; i <= nr; i++) q[ql - 1 + nl + i] = rq[i]; //将右儿子操作数组拷贝到q中原来的下标是[ql-1+nl+i]
//继续二分左右儿子
solve(l, mid, ql, ql + nl - 1), solve(mid + 1, r, ql + nl, qr);
}
int main() {
int l, r, k, c = 0, qc = 0;
n = read(), qc = read();
for (int i = 1; i <= n; i++) a[i] = read(), q[++c] = {1, a[i], i}; // op=1:插入,a[i]:值i:位置
for (int i = 1; i <= qc; i++) {
l = read(), r = read(), k = read();
q[++c] = {2, l, r, k, i}; // op=2查询,[l,r]:查询范围,k:第k小,i:查询序号
}
//整体二分
solve(-1e9, 1e9, 1, c); //值域[-1e9,1e9],二分查询区间[1,n+m]
//结果
for (int i = 1; i <= qc; i++) printf("%d\n", ans[i]);
return 0;
}