Pagini recente » Cod sursa (job #2174422) | Cod sursa (job #2866096) | Cod sursa (job #2471807) | Cod sursa (job #2621521) | Cod sursa (job #2635241)
#include <bits/stdc++.h>
using namespace std;
template<typename T> struct rmq {
vector<T> v;
int n; static const int b = 30;
vector<int> mask, t;
int op(int x, int y) { return v[x] < v[y] ? x : y; }
int msb(int x) { return __builtin_clz(1)-__builtin_clz(x); }
int small(int r, int sz = b) { return r-msb(mask[r]&((1<<sz)-1)); }
rmq(const vector<T>& v_) : v(v_), n(v.size()), mask(n), t(n) {
for (int i = 0, at = 0; i < n; mask[i++] = at |= 1) {
at = (at<<1)&((1<<b)-1);
while (at and op(i, i-msb(at&-at)) == i) at ^= at&-at;
}
for (int i = 0; i < n/b; i++) t[i] = small(b*i+b-1);
for (int j = 1; (1<<j) <= n/b; j++) for (int i = 0; i+(1<<j) <= n/b; i++)
t[n/b*j+i] = op(t[n/b*(j-1)+i], t[n/b*(j-1)+i+(1<<(j-1))]);
}
T query(int l, int r) {
if (r-l+1 <= b) return v[small(r, r-l+1)];
int ans = op(small(l+b-1), small(r));
int x = l/b+1, y = r/b-1;
if (x <= y) {
int j = msb(y-x+1);
ans = op(ans, op(t[n/b*j+x], t[n/b*j+y-(1<<j)+1]));
}
return v[ans];
}
};
int main (void) {
ifstream fin ("rmq.in");
ofstream fout ("rmq.out");
int n, m;
fin >> n >> m;
vector <int> v;
for (; n; --n) {
fin >> m;
v.push_back(m);
}
rmq <int> RMQ(v);
while (fin >> n >> m)
fout << RMQ.query(n-1, m-1) << '\n';
return 0;
}