| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 795363 | Josia | Horses (IOI15_horses) | C++17 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include "horses.h"
#include <bits/stdc++.h>
using namespace std;
#define ll long long
// #define int long long
constexpr ll mod = 1e9+7;
struct seg {
vector<int> tree;
array<int, 2000000> tree;
void init(int n) {
// tree.assign(n*4, 0);
}
void update(int v, int rl, int rr, int pos, int x) {
if (rl == rr) {
tree[v] = x;
return;
}
int rm = (rl + rr)/2;
if (pos <= rm) update(v*2, rl, rm, pos, x);
else update(v*2+1, rm+1, rr, pos, x);
tree[v] = max(tree[v*2], tree[v*2+1]);
}
int query(int v, int rl, int rr, int ql, int qr) {
if (ql > qr) return 0;
if (rl == ql && rr == qr) return tree[v];
int rm = (rl + rr)/2;
return max(query(v*2, rl, rm, ql, min(qr, rm)), query(v*2+1, rm+1, rr, max(ql, rm+1), qr));
}
};
struct segY {
vector<pair<int, int>> tree;
void init(int n) {
tree.assign(n*4, {0, 0});
}
void update(int v, int rl, int rr, int pos, int x) {
if (rl == rr) {
tree[v] = {x, pos};
return;
}
int rm = (rl + rr)/2;
if (pos <= rm) update(v*2, rl, rm, pos, x);
else update(v*2+1, rm+1, rr, pos, x);
tree[v] = max(tree[v*2], tree[v*2+1]);
}
pair<int, int> query(int v, int rl, int rr, int ql, int qr) {
if (ql > qr) return {0, -1};
if (rl == ql && rr == qr) return tree[v];
int rm = (rl + rr)/2;
return max(query(v*2, rl, rm, ql, min(qr, rm)), query(v*2+1, rm+1, rr, max(ql, rm+1), qr));
}
};
ll mult(ll a, ll b) {
int res = a*b;
if (res >= mod) res%=mod;
return res;
}
struct seg2 {
vector<ll> tree;
void init(int n) {
tree.assign(n*4, 0);
}
void update(int v, int rl, int rr, int pos, int x) {
if (rl == rr) {
tree[v] = x;
return;
}
int rm = (rl + rr)/2;
if (pos <= rm) update(v*2, rl, rm, pos, x);
else update(v*2+1, rm+1, rr, pos, x);
tree[v] = mult(tree[v*2], tree[v*2+1]);
}
ll query(int v, int rl, int rr, int ql, int qr) {
if (ql > qr) return 1;
if (rl == ql && rr == qr) return tree[v];
int rm = (rl + rr)/2;
return mult(query(v*2, rl, rm, ql, min(qr, rm)), query(v*2+1, rm+1, rr, max(ql, rm+1), qr));
}
};
seg tree;
segY treeY;
seg2 tree2;
int N;
vector<ll> X, Y;
struct getSol {
int sol = 0;
int BS(int pos) {
if (pos == 0) return -1;
int l = 0, r = pos-1;
while (l<r) {
int m = (l+r+1)/2;
if (tree.query(1, 0, N-1, m, pos-1) > 1) {
l = m;
} else {
r = m-1;
}
}
return l;
}
int BSinv(int pos) {
if (pos == N-1) return N-1;
int l = pos+1, r = N-1;
while (l<r) {
int m = (l+r+1)/2;
if (tree.query(1, 0, N-1, pos+1, m) > 1) {
r = m-1;
} else {
l = m;
}
}
return l;
}
int findInd() {
int currInd = N-1;
ll currProd = 1;
for (int i = N-1; i>=0; i = BS(i)) {
auto bestSell = treeY.query(1, 0, N-1, i, BSinv(i));
if (currProd*Y[currInd] <= bestSell.first) {currInd = bestSell.second; currProd=1;}
currProd *= X[i];
if (currProd*Y[currInd] > 1e9) break;
}
return currInd;
}
getSol() {
int ind = findInd();
sol = (tree2.query(1, 0, N-1, 0, ind) * Y[ind])%mod;
}
};
signed init(signed _N, signed _X[], signed _Y[]) {
N = _N;
X.resize(N);
Y.resize(N);
for (int i = 0; i<N; i++) X[i] = _X[i];
for (int i = 0; i<N; i++) Y[i] = _Y[i];
tree.init(N);
treeY.init(N);
tree2.init(N);
for (int i = 0; i<N; i++) {
tree.update(1, 0, N-1, i, X[i]);
treeY.update(1, 0, N-1, i, Y[i]);
tree2.update(1, 0, N-1, i, X[i]);
}
return getSol().sol;
}
signed updateX(signed pos, signed val) {
tree.update(1, 0, N-1, pos, val);
tree2.update(1, 0, N-1, pos, val);
X[pos] = val;
return getSol().sol;
}
signed updateY(signed pos, signed val) {
treeY.update(1, 0, N-1, pos, val);
Y[pos] = val;
return getSol().sol;
}