| # | 제출 시각 | 아이디 | 문제 | 언어 | 결과 | 실행 시간 | 메모리 |
|---|---|---|---|---|---|---|---|
| 1312851 | nikaa123 | 말 (IOI15_horses) | C++20 | 0 ms | 0 KiB |
#include <bits/stdc++.h>
#include "horses.h"
#define int long long
using namespace std;
const int inf = INT_MAX;
const int mod = 1000000007;
const int S = 5e5+5;
int n;
int x[S],y[S];
int pref[S];
int t[4*S];
int lazy[4*S];
void applay(int x, int val) {
t[x] = (t[x] * val) % mod;
lazy[x] = (lazy[x] * val) % mod;
}
void push(int x) {
if (lazy[x] != 1) {
applay(x*2,lazy[x]);
applay(x*2+1,lazy[x]);
lazy[x] = 1;
}
}
void update(int node, int l, int r, int L, int R, int val) {
if (r < L || l > R) return;
if (l >= L && r <= R) {
applay(node,val);
return;
}
push(node);
int mid = (l+r)/2;
update(node*2,l,mid,L,R,val);
update(node*2+1,mid+1,r,L,R,val);
t[node] = max(t[node*2],t[node*2+1]);
}
int getans(int node, int l, int r, int L, int R) {
if (r < L || l > R) return -inf;
if (l >= L && r <= R) return t[node];
push(node);
int mid = (l+r)/2;
return max(getans(node*2,l,mid,L,R),getans(node*2+1,mid+1,r,L,R));
}
int inv(int x, int k = mod - 2) {
int res = 1;
while (k) {
if (k&1) {
res = (res * x) % mod;
}
x = (x * x) % mod;
k >>= 1;
}
return res;
}
int init(int N, int X[], int Y[]) {
n = N;
for (int i = 0; i < n; i++) {
x[i] = X[i];
y[i] = Y[i];
}
pref[0] = X[0];
for (int i = 1; i < n; i++) {
pref[i] = (pref[i-1] * x[i]) % mod;
}
for (int i = 0; i < n; i++) {
pref[i] = (pref[i] * y[i]) % mod;
}
for (int i = 1; i <= 4*n; i++) {
lazy[i] = 1;
t[i] = 1;
}
for (int i = 1; i <= n; i++) {
update(1,1,n,i,i,pref[i-1]);
}
return getans(1,1,n,1,n);
}
int updateX(int pos, int val) {
update(1,1,n,pos+1,n,inv(x[pos]));
x[pos] = val;
update(1,1,n,pos+1,n,x[pos]);
return getans(1,1,n,1,n);
}
int updateY(int pos, int val) {
update(1,1,n,pos+1,pos+1,inv(y[pos]));
y[pos] = val;
update(1,1,n,pos+1,pos+1,y[pos]);
return getans(1,1,n,1,n);
}