| # |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
| 785435 |
2023-07-17T09:06:38 Z |
NothingXD |
Horses (IOI15_horses) |
C++17 |
|
149 ms |
29888 KB |
#include "horses.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef complex<ld> point;
typedef __uint128_t L;
struct FastMod {
ull b, m;
FastMod(ull b) : b(b), m(ull((L(1) << 64) / b)) {}
ull reduce(ull a) {
ull q = (ull)((L(m) * a) >> 64);
ull r = a - q * b; // can be proven that 0 <= r < 2*b
return r >= b ? r - b : r;
}
};
FastMod FM(1e9+7);
void debug_out(){cerr << endl;}
template<typename Head, typename... Tail>
void debug_out(Head H, Tail... T){
cout << H << " ";
debug_out(T...);
}
#define debug(...) cerr << "(" << #__VA_ARGS__ << "): ", debug_out(__VA_ARGS__)
#define F first
#define S second
#define all(x) x.begin(), x.end()
#define MP(x, y) make_pair(x, y)
const int maxn = 5e5 + 10;
const int mod = 1e9 + 7;
int n;
ll x[maxn], y[maxn];
ll dp[maxn << 2][2];
bool of[maxn << 2];
int find(int v, int l, int r, int tmp){
if (!of[v] && 1ll * tmp * dp[v][1] < mod) return -1;
if (l + 1 == r) return l;
int mid = (l + r) >> 1;
int lc = v << 1;
int rc = lc | 1;
int res = find(rc, mid, r, tmp);
if (res == -1){
tmp *= dp[rc][1];
res = find(lc, l, mid, tmp);
}
return res;
}
void build2(int v, int l, int r){
if (l + 1 == r){
dp[v][0] = x[l] * y[l];
dp[v][1] = x[l];
return;
}
int mid = (l + r) >> 1;
int lc = v << 1;
int rc = lc | 1;
build2(lc, l, mid);
build2(rc, mid, r);
dp[v][0] = max(dp[lc][0], dp[lc][1] * dp[rc][0]);
dp[v][1] = dp[lc][1] * dp[rc][1];
if (dp[v][1] >= mod || of[lc] || of[rc]) of[v] = true;
dp[v][1] = FM.reduce(dp[v][1]);
}
void change2(int v, int l, int r, int idx){
if (l + 1 == r){
dp[v][0] = x[l] * y[l];
dp[v][1] = x[l];
return;
}
int mid = (l + r) >> 1;
int lc = v << 1;
int rc = lc | 1;
if (idx < mid) change2(lc, l, mid, idx);
else change2(rc, mid, r, idx);
dp[v][0] = max(dp[lc][0], dp[lc][1] * dp[rc][0]);
dp[v][1] = dp[lc][1] * dp[rc][1];
if (dp[v][1] >= mod || of[lc] || of[rc]) of[v] = true;
dp[v][1] = FM.reduce(dp[v][1]);
}
pll get2(int v, int l, int r, int ql, int qr){
if (ql <= l && r <= qr) return MP(dp[v][0], dp[v][1]);
int mid = (l + r) >> 1;
int lc = v << 1;
int rc = lc | 1;
pll a = {0, 1};
pll b = {0, 1};
if (qr > l && ql < mid) a = get2(lc, l, mid, ql, qr);
if (qr > mid && ql < r) b = get2(rc, mid, r, ql, qr);
return MP(max(a.F, a.S * b.F), FM.reduce(a.S * b.S));
}
int Calc(){
int idx = find(1, 0, n, 1);
if (idx == -1) idx = 0;
assert(idx < n-1);
int tmp = get2(1, 0, n, 0, idx+1).S;
ll tmp2 = FM.reduce(max(y[idx], get2(1, 0, n, idx+1, n).F));
return FM.reduce(1ll * tmp * tmp2);
}
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];
}
build2(1, 0, n);
return Calc();
}
int updateX(int pos, int val) {
x[pos] = val;
change2(1, 0, n, pos);
return Calc();
}
int updateY(int pos, int val) {
y[pos] = val;
change2(1, 0, n, pos);
return Calc();
}
Compilation message
horses.cpp: In constructor 'FastMod::FastMod(ull)':
horses.cpp:16:14: warning: declaration of 'b' shadows a member of 'FastMod' [-Wshadow]
16 | FastMod(ull b) : b(b), m(ull((L(1) << 64) / b)) {}
| ~~~~^
horses.cpp:15:6: note: shadowed declaration is here
15 | ull b, m;
| ^
horses.cpp: In constructor 'FastMod::FastMod(ull)':
horses.cpp:16:14: warning: declaration of 'b' shadows a member of 'FastMod' [-Wshadow]
16 | FastMod(ull b) : b(b), m(ull((L(1) << 64) / b)) {}
| ~~~~^
horses.cpp:15:6: note: shadowed declaration is here
15 | ull b, m;
| ^
horses.cpp: In constructor 'FastMod::FastMod(ull)':
horses.cpp:16:14: warning: declaration of 'b' shadows a member of 'FastMod' [-Wshadow]
16 | FastMod(ull b) : b(b), m(ull((L(1) << 64) / b)) {}
| ~~~~^
horses.cpp:15:6: note: shadowed declaration is here
15 | ull b, m;
| ^
horses.cpp: In function 'int find(int, int, int, int)':
horses.cpp:56:7: warning: conversion from 'll' {aka 'long long int'} to 'int' may change value [-Wconversion]
56 | tmp *= dp[rc][1];
| ~~~~^~~~~~~~~~~~
horses.cpp: In function 'int Calc()':
horses.cpp:36:11: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
36 | #define S second
| ^
horses.cpp:112:36: note: in expansion of macro 'S'
112 | int tmp = get2(1, 0, n, 0, idx+1).S;
| ^
horses.cpp:114:18: warning: conversion from 'ull' {aka 'long long unsigned int'} to 'int' may change value [-Wconversion]
114 | return FM.reduce(1ll * tmp * tmp2);
| ~~~~~~~~~^~~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
2 ms |
468 KB |
Execution killed with signal 6 |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
1 ms |
468 KB |
Execution killed with signal 6 |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
89 ms |
29384 KB |
Output is correct |
| 2 |
Correct |
149 ms |
29864 KB |
Output is correct |
| 3 |
Correct |
140 ms |
29872 KB |
Output is correct |
| 4 |
Correct |
130 ms |
29888 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
2 ms |
468 KB |
Execution killed with signal 6 |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
1 ms |
468 KB |
Execution killed with signal 6 |
| 2 |
Halted |
0 ms |
0 KB |
- |
