| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 1039917 | Zicrus | 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 <bits/stdc++.h>
#include "horses.h"
using namespace std;
typedef long long ll;
namespace Sol2 {
ll n, pow2;
vector<ll> segMul, segMax;
vector<bool> segOF;
vector<ll> x, y;
vector<ll> lnk;
vector<ll> effY;
#define MOD (1000000007)
int getPrev2Id(int i) {
// TODO (inc)
// If no 2, return id 0
// i can be negative!!!
if (i < 0) return 0;
i += pow2;
while (segMul[i] == 1 && !segOF[i]) {
if (!(i & 1)) {
if ((i & (i-1)) == 0) return 0;
i--;
}
i /= 2;
}
// now search down
while (i < pow2) {
if (segMul[2*i+1] == 1 && !segOF[2*i+1]) i = 2*i;
else i = 2*i+1;
}
return i-pow2;
}
int getMax(ll low, ll high) {
low += pow2; high += pow2;
ll res = 0;
while (low <= high) {
if (low & 1) res = max(res, segMax[low++]);
if (!(high & 1)) res = max(res, segMax[high--]);
low /= 2; high /= 2;
}
return res;
}
void setX(int pos, int val) {
if (val == x[pos]) return;
int savedPos = pos;
int old = x[pos];
x[pos] = val;
pos += pow2;
segMul[pos] = val;
pos /= 2;
while (pos) {
segMul[pos] = segMul[2*pos] * segMul[2*pos+1];
if (segOF[2*pos] || segOF[2*pos+1] || segMul[pos] > MOD) {
segMul[pos] %= MOD;
segOF[pos] = true;
}
else {
segOF[pos] = false;
}
pos /= 2;
}
pos = savedPos;
if (val == 1) {
ll prev2 = getPrev2Id(pos-1);
lnk[prev2] = lnk[pos];
effY[prev2] = getMax(prev2, lnk[prev2]-1);
return;
}
if (old > 1) {
effY[pos] = getMax(pos, lnk[pos]-1);
return;
}
if (pos == 0) {
effY[pos] = getMax(pos, lnk[pos]-1);
return;
}
ll prev2 = getPrev2Id(pos-1);
lnk[pos] = lnk[prev2];
effY[pos] = getMax(pos, lnk[pos]-1);
lnk[prev2] = pos;
effY[prev2] = getMax(prev2, lnk[prev2]-1);
return;
}
void setY(int pos, int val) {
ll i = pos;
y[i] = val;
i += pow2;
segMax[i] = val;
i /= 2;
while (i) {
segMax[i] = max(segMax[2*i], segMax[2*i+1]);
i /= 2;
}
ll prev2 = getPrev2Id(pos-1);
effY[prev2] = getMax(prev2, lnk[prev2]-1);
effY[pos] = getMax(pos, lnk[pos]-1);
return;
}
int getOFId(int i = 1, ll prod = 1) {
if (i >= pow2) return i-pow2;
if (segOF[2*i+1] || segMul[2*i+1] * prod >= MOD) return getOFId(2*i+1, prod);
return getOFId(2*i, prod * segMul[2*i+1]);
}
int getMulMod(int i) {
int low = pow2, high = pow2+i;
ll res = 1;
while (low <= high) {
if (low & 1) res = (res * segMul[low++]) % MOD;
if (!(high & 1)) res = (res * segMul[high--]) % MOD;
low /= 2; high /= 2;
}
return res % MOD;
}
int calc() {
ll ofId = getOFId();
ll mx = effY[ofId];
ll offCnt = getMulMod(ofId);
ll tCnt = 1;
ll mxRes = (effY[ofId] * offCnt) % MOD;
ofId = lnk[ofId];
if (!segOF[1]) {
offCnt = 1;
ofId = 0;
mx = 0;
}
for (int i = ofId; i < n; i = lnk[i]) {
offCnt *= x[i];
offCnt %= MOD;
tCnt *= x[i];
ll val = tCnt * effY[i];
if (val > mx) {
mx = val;
mxRes = (offCnt * effY[i]) % MOD;
}
}
return mxRes;
}
int init(int N, int X[], int Y[]) {
n = N; pow2 = 1ll << (ll)ceil(log2(n));
x = vector<ll>(n);
y = vector<ll>(n);
lnk = vector<ll>(n);
effY = vector<ll>(n);
ll lastNon1 = n;
for (int i = n-1; i >= 0; i--) {
x[i] = X[i];
y[i] = Y[i];
lnk[i] = lastNon1;
if (x[i] > 1) lastNon1 = i;
}
segMul = vector<ll>(2*pow2, 1);
segMax = vector<ll>(2*pow2, 1);
segOF = vector<bool>(2*pow2);
for (int i = 0; i < n; i++) {
segMul[pow2+i] = x[i];
segMax[pow2+i] = y[i];
}
for (int i = pow2-1; i > 0; i--) {
segMul[i] = segMul[2*i] * segMul[2*i+1];
if (segOF[2*i] || segOF[2*i+1] || segMul[i] >= MOD) {
segMul[i] %= MOD;
segOF[i] = true;
}
segMax[i] = max(segMax[2*i], segMax[2*i+1]);
}
for (int i = 0; i < n; i = lnk[i]) {
if (lnk[i] == i+1) effY[i] = y[i];
else effY[i] = getMax(i, lnk[i]-1);
}
return calc();
}
int updateX(int pos, int val) {
setX(pos, val);
ll val111 = effY[3493];
ll id = find(y.begin(), y.end(), 999825195) - y.begin();
ll v = calc();
return v;
}
int updateY(int pos, int val) {
bool hi = true;
setY(pos, val);
ll v = calc();
return v;
}