oj.uz

Submission #738980

# Submission time Handle Problem Language Result Execution time Memory
738980 2023-05-09T18:02:23 Z shoryu386 Horses (IOI15_horses) C++17
54 / 100
 1500 ms 26076 KB 
#include <bits/stdc++.h>
using namespace std;
#define MOD 1000000007LL
#include "horses.h"

//hypothesis 1: There is no point in keeping a partial amount of horses. Sell all, or don't bother.
//Let's test this.
//Ok, should be confirmed (passed subtask 1)

//now, running product of X can be really big
//we need to determine the largest value in meow, where meow[i] = Y[i] * prefixProdX[i];
//honestly even Y[i] can be really big (10^9 for both X and Y)

//I also don't really want to touch floating point
//let our two comparison indices be A and B
//without loss of generality, let A < B
//then meow[A] = Y[A] * prefixProdX[A], meow[B] = Y[B] * prefixProdX[B]
//meow[A] < meow[B] iff
//Y[A] * prefixProdX[A] < Y[B] * prefixProdX[B]
//Y[A] < Y[B] * prefixProdX[B] / prefixProdX[A]
//Y[A] < Y[B] * rangeProdX(A+1, B)
//hmm both Y[A] and Y[B] are bounded by 10^9
//meaning if rangeProdX(A+1, B) ever exceeds 10^9, we can safely say meow[B] is greater

//Y is also bounded by 1

#define int long long
#define actlint int32_t
actlint *X, *Y;
int N;
bool st3 = true;

#define MAXN 500001
#define makeMid int mid = (s+e)/2
#define lc(x) (2*x)
#define rc(x) (2*x+1)
#define parent(x) (x/2)
typedef int stdata;
stdata ST[4*MAXN+1] = {0};
inline stdata combine(stdata x, stdata y){
	return (x*y)%MOD;
}
void pointSet(int x, stdata y, int index=1, int s=0, int e=N-1){
	makeMid;
	if (s==e){ ST[index] = y; return; }
	if (x <= mid) pointSet(x, y, lc(index), s, mid);
	else pointSet(x, y, rc(index), mid+1, e);
	ST[index] = combine(ST[lc(index)], ST[rc(index)]);
}

void pointAdd(int x, stdata y, int index=1, int s=0, int e=N-1){
	makeMid;
	if (s==e){ ST[index] += y; return; }
	if (x <= mid) pointAdd(x, y, lc(index), s, mid);
	else pointAdd(x, y, rc(index), mid+1, e);
	ST[index] = combine(ST[lc(index)], ST[rc(index)]);
}

stdata query(int x, int y, int index=1, int s=0, int e=N-1){
	makeMid;
	if (s==x && e==y) return ST[index];
	if (x <= mid && y > mid) return combine(query(x, mid, lc(index), s, mid), query(mid+1, y, rc(index), mid+1, e));
	else if (x <= mid) return query(x, y, lc(index), s, mid);
	else return query(x, y, rc(index), mid+1, e);
}


int calc(){
	//this is bottleneck of code
	//this takes O(N) time, which is too long since we cannot afford O(NM)
	
	//problem that this is meant to solve:
	//find max of Y[i] * prefixProdX[i] (in log n time?)
	
	long long best = 0;
	long long run = 1;
	
	long long init = 0;
	if (st3) init = max(N-33LL, 0LL), best = max(N-33LL, 0LL);
	
	for (int i = init; i < N; i++){
		run *= X[i];
		if ((int)Y[best] < (int)Y[i] * run){
			best = i;
			run = 1;
		}
	}
	
	run = query(0, best);
	
	run *= Y[best]; run %= MOD;
	
	return run;
}


actlint init(actlint hmN, actlint hmX[], actlint hmY[]) {
	N = hmN;
	X = hmX; Y = hmY;
	for (int i = 0; i < N; i++){
		if (X[i] < 2) st3 = false;
		pointSet(i, X[i]);
	}
	return calc();
}

actlint updateX(actlint pos, actlint val) {	
	X[pos] = val;
	if (val < 2) st3 = false;
	pointSet(pos, val);
	return calc();
}

actlint updateY(actlint pos, actlint val) {
	Y[pos] = val;
	return calc();
}

Compilation message

horses.cpp: In function 'int32_t init(int32_t, int32_t*, int32_t*)':
horses.cpp:104:13: warning: conversion from 'long long int' to 'int32_t' {aka 'int'} may change value [-Wconversion]
  104 |  return calc();
      |         ~~~~^~
horses.cpp: In function 'int32_t updateX(int32_t, int32_t)':
horses.cpp:111:13: warning: conversion from 'long long int' to 'int32_t' {aka 'int'} may change value [-Wconversion]
  111 |  return calc();
      |         ~~~~^~
horses.cpp: In function 'int32_t updateY(int32_t, int32_t)':
horses.cpp:116:13: warning: conversion from 'long long int' to 'int32_t' {aka 'int'} may change value [-Wconversion]
  116 |  return calc();
      |         ~~~~^~

Subtask #1
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 312 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 1 ms 312 KB Output is correct
7 Correct 1 ms 312 KB Output is correct
8 Correct 0 ms 212 KB Output is correct
9 Correct 1 ms 212 KB Output is correct
10 Correct 1 ms 312 KB Output is correct
11 Correct 1 ms 212 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 1 ms 212 KB Output is correct
14 Correct 1 ms 212 KB Output is correct
15 Correct 1 ms 212 KB Output is correct
16 Correct 1 ms 212 KB Output is correct
17 Correct 1 ms 212 KB Output is correct
18 Correct 1 ms 212 KB Output is correct
19 Correct 1 ms 212 KB Output is correct
20 Correct 1 ms 212 KB Output is correct

Subtask #2
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
6 Correct 1 ms 212 KB Output is correct
7 Correct 0 ms 212 KB Output is correct
8 Correct 0 ms 316 KB Output is correct
9 Correct 1 ms 212 KB Output is correct
10 Correct 1 ms 212 KB Output is correct
11 Correct 1 ms 312 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 1 ms 316 KB Output is correct
14 Correct 1 ms 316 KB Output is correct
15 Correct 1 ms 312 KB Output is correct
16 Correct 1 ms 212 KB Output is correct
17 Correct 1 ms 212 KB Output is correct
18 Correct 1 ms 212 KB Output is correct
19 Correct 1 ms 292 KB Output is correct
20 Correct 1 ms 212 KB Output is correct
21 Correct 0 ms 212 KB Output is correct
22 Correct 1 ms 212 KB Output is correct
23 Correct 5 ms 340 KB Output is correct
24 Correct 5 ms 320 KB Output is correct
25 Correct 5 ms 340 KB Output is correct
26 Correct 5 ms 340 KB Output is correct
27 Correct 5 ms 340 KB Output is correct
28 Correct 5 ms 340 KB Output is correct
29 Correct 5 ms 340 KB Output is correct
30 Correct 5 ms 428 KB Output is correct
31 Correct 5 ms 340 KB Output is correct
32 Correct 5 ms 340 KB Output is correct

Subtask #3
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 158 ms 17188 KB Output is correct
2 Correct 192 ms 26076 KB Output is correct
3 Correct 153 ms 17120 KB Output is correct
4 Correct 198 ms 20932 KB Output is correct

Subtask #4
0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 1 ms 212 KB Output is correct
7 Correct 1 ms 212 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 1 ms 212 KB Output is correct
10 Correct 1 ms 212 KB Output is correct
11 Correct 1 ms 316 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 1 ms 212 KB Output is correct
14 Correct 1 ms 212 KB Output is correct
15 Correct 1 ms 212 KB Output is correct
16 Correct 1 ms 212 KB Output is correct
17 Correct 1 ms 212 KB Output is correct
18 Correct 1 ms 212 KB Output is correct
19 Correct 1 ms 312 KB Output is correct
20 Correct 1 ms 212 KB Output is correct
21 Correct 1 ms 212 KB Output is correct
22 Correct 1 ms 212 KB Output is correct
23 Correct 6 ms 340 KB Output is correct
24 Correct 5 ms 324 KB Output is correct
25 Correct 6 ms 340 KB Output is correct
26 Correct 6 ms 340 KB Output is correct
27 Correct 6 ms 340 KB Output is correct
28 Correct 6 ms 340 KB Output is correct
29 Correct 5 ms 468 KB Output is correct
30 Correct 5 ms 340 KB Output is correct
31 Correct 4 ms 340 KB Output is correct
32 Correct 5 ms 340 KB Output is correct
33 Execution timed out 1560 ms 16356 KB Time limit exceeded
34 Halted 0 ms 0 KB -

Subtask #5
0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 1 ms 212 KB Output is correct
7 Correct 1 ms 212 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 1 ms 312 KB Output is correct
10 Correct 1 ms 212 KB Output is correct
11 Correct 1 ms 212 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 1 ms 212 KB Output is correct
14 Correct 1 ms 212 KB Output is correct
15 Correct 1 ms 308 KB Output is correct
16 Correct 1 ms 212 KB Output is correct
17 Correct 0 ms 212 KB Output is correct
18 Correct 0 ms 212 KB Output is correct
19 Correct 1 ms 312 KB Output is correct
20 Correct 1 ms 212 KB Output is correct
21 Correct 1 ms 340 KB Output is correct
22 Correct 1 ms 212 KB Output is correct
23 Correct 5 ms 340 KB Output is correct
24 Correct 5 ms 340 KB Output is correct
25 Correct 5 ms 340 KB Output is correct
26 Correct 6 ms 348 KB Output is correct
27 Correct 5 ms 340 KB Output is correct
28 Correct 5 ms 324 KB Output is correct
29 Correct 5 ms 340 KB Output is correct
30 Correct 5 ms 340 KB Output is correct
31 Correct 5 ms 340 KB Output is correct
32 Correct 5 ms 340 KB Output is correct
33 Correct 147 ms 17112 KB Output is correct
34 Correct 196 ms 25980 KB Output is correct
35 Correct 157 ms 17164 KB Output is correct
36 Correct 203 ms 21000 KB Output is correct
37 Execution timed out 1555 ms 16356 KB Time limit exceeded
38 Halted 0 ms 0 KB -