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| #include <map>
#include <cstdio>
#include <algorithm>
using namespace std;
int getint() {
int r = 0, k = 1; char c = getchar();
for (; c < '0' || c > '9'; c = getchar()) if (c == '-') k = -1;
for (; '0' <= c && c <= '9'; c = getchar()) r = r * 10 - '0' + c;
return r * k;
}
map<int, int> M;
const int N = 500005;
const int mxlog = 30;
int n, m, ans, K, H[N], siz[N * mxlog], lc[N * mxlog], rc[N * mxlog], tot, cnt, a[N], root[N], l, r;
void sgtQuery(int x, int y, int l, int r) {
if (l == r) {
ans = l;
return;
}
int mid = (l + r) >> 1;
if (siz[lc[x]] - siz[lc[y]] > K) sgtQuery(lc[x], lc[y], l, mid);
if (siz[rc[x]] - siz[rc[y]] > K) sgtQuery(rc[x], rc[y], mid+1, r);
}
void sgtChange(int &x, int y, int l, int r, int pos) {
x = ++tot;
lc[x] = lc[y];
rc[x] = rc[y];
siz[x] = siz[y] + 1;
if (l == r) return;
int mid = (l + r) >> 1;
if (pos <= mid) sgtChange(lc[x], lc[y], l, mid, pos);
else sgtChange(rc[x], rc[y], mid+1, r, pos);
}
int main() {
n = getint(); m = getint();
for (int i = 1; i <= n; ++i) {
a[i] = getint();
M[a[i]] = 0;
}
for (map<int, int>::iterator it = M.begin(); it != M.end(); ++it) {
it->second = ++cnt;
H[cnt] = it->first;
}
for (int i = 1; i <= n; ++i)
sgtChange(root[i], root[i-1], 1, cnt, M[a[i]]);
for (int i = 1; i <= m; ++i) {
l = getint(); r = getint(); ans = 0; K = (r - l + 1) >> 1;
sgtQuery(root[r], root[l-1], 1, cnt);
printf("%d\n", H[ans]);
}
}
|