Submission #893703

#	Time	Username	Problem	Language	Result	Execution time	Memory
893703		yellowtoad	Horses (IOI15_horses)	C++17	17 / 100	1033 ms	43576 KiB

horses

#include "horses.h"
#include <iostream>
using namespace std;

const long long mod = 1e9+7;
long long n, a[500010], b[500010], node[2000010][3];
bool done;

/*
0: x product
1: max x
2: max y
*/

void build(int id, int x, int y) {
	if (x == y) {
		node[id][0] = a[x]%mod;
		node[id][1] = a[x];
		node[id][2] = b[x];
		return;
	}
	int mid = (x+y)/2;
	build(id*2,x,mid);
	build(id*2+1,mid+1,y);
	node[id][0] = (node[id*2][0]*node[id*2+1][0])%mod;
	node[id][1] = max(node[id*2][1],node[id*2+1][1]);
	node[id][2] = max(node[id*2][2],node[id*2+1][2]);
}

void update(int id, int jd, int x, int y, int pos, int val) {
	if (x == y) {
		node[id][jd] = val;
		return;
	}
	int mid = (x+y)/2;
	if (pos <= mid) update(id*2,jd,x,mid,pos,val);
	else update(id*2+1,jd,mid+1,y,pos,val);
	if (jd == 0) node[id][0] = (node[id*2][0]*node[id*2+1][0])%mod;
	else if (jd == 1) node[id][1] = max(node[id*2][1],node[id*2+1][1]);
	else node[id][2] = max(node[id*2][2],node[id*2+1][2]);
}

int nxt(int id, int x, int y, int r) {
	if (x > r) return 0;
	if (node[id][1] == 1) return 0;
	if (x == y) {
		done = 1;
		return x;
	}
	int mid = (x+y)/2, tmp = nxt(id*2+1,mid+1,y,r);
	if (!done) return nxt(id*2,x,mid,r);
	else return tmp;
}

int find_max(int id, int x, int y, int l, int r) {
	if ((l <= x) && (y <= r)) return node[id][2];
	if ((y < l) || (r < x)) return 0;
	int mid = (x+y)/2;
	return max(find_max(id*2,x,mid,l,r),find_max(id*2+1,mid+1,y,l,r));
}

int find_pro(int id, int x, int y, int l, int r) {
	if ((l <= x) && (y <= r)) return node[id][0];
	if ((y < l) || (r < x)) return 1;
	int mid = (x+y)/2;
	return (find_pro(id*2,x,mid,l,r)*find_pro(id*2+1,mid+1,y,l,r))%mod;
}

int solve() {
	int cur = nxt(1,1,n,n)-1, lst = n, maxx = 1;
	while (maxx <= 1e9+7) {
		maxx = max(maxx,find_max(1,1,n,cur+1,lst));
		lst = cur+1;
		maxx *= find_pro(1,1,n,lst,lst);
		done = 0;
		if (cur == -1) break;
		cur = nxt(1,1,n,cur)-1;
	}
	return ((maxx%mod)*find_pro(1,1,n,1,cur))%mod;
}

int init(int N, int X[], int Y[]) {
	n = N;
	for (int i = 0; i < n; i++) a[i+1] = X[i], b[i+1] = Y[i];
	build(1,1,n);
	return solve();
}

int updateX(int pos, int val) {
	pos++;
	update(1,0,1,n,pos,val%mod);
	update(1,1,1,n,pos,val);
	return solve();
}

int updateY(int pos, int val) {
	pos++;
	update(1,2,1,n,pos,val);
	return solve();
}

Compilation message (stderr)

horses.cpp: In function 'int find_max(int, int, int, int, int)':
horses.cpp:56:45: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
   56 |  if ((l <= x) && (y <= r)) return node[id][2];
      |                                   ~~~~~~~~~~^
horses.cpp: In function 'int find_pro(int, int, int, int, int)':
horses.cpp:63:45: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
   63 |  if ((l <= x) && (y <= r)) return node[id][0];
      |                                   ~~~~~~~~~~^
horses.cpp: In function 'int solve()':
horses.cpp:70:20: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
   70 |  int cur = nxt(1,1,n,n)-1, lst = n, maxx = 1;
      |                    ^
horses.cpp:70:22: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
   70 |  int cur = nxt(1,1,n,n)-1, lst = n, maxx = 1;
      |                      ^
horses.cpp:70:34: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
   70 |  int cur = nxt(1,1,n,n)-1, lst = n, maxx = 1;
      |                                  ^
horses.cpp:72:32: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
   72 |   maxx = max(maxx,find_max(1,1,n,cur+1,lst));
      |                                ^
horses.cpp:74:24: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
   74 |   maxx *= find_pro(1,1,n,lst,lst);
      |                        ^
horses.cpp:77:17: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
   77 |   cur = nxt(1,1,n,cur)-1;
      |                 ^
horses.cpp:79:34: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
   79 |  return ((maxx%mod)*find_pro(1,1,n,1,cur))%mod;
      |                                  ^
horses.cpp:79:43: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
   79 |  return ((maxx%mod)*find_pro(1,1,n,1,cur))%mod;
      |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~
horses.cpp: In function 'int init(int, int*, int*)':
horses.cpp:85:12: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
   85 |  build(1,1,n);
      |            ^
horses.cpp: In function 'int updateX(int, int)':
horses.cpp:91:15: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
   91 |  update(1,0,1,n,pos,val%mod);
      |               ^
horses.cpp:92:15: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
   92 |  update(1,1,1,n,pos,val);
      |               ^
horses.cpp: In function 'int updateY(int, int)':
horses.cpp:98:15: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
   98 |  update(1,2,1,n,pos,val);
      |               ^

• Subtask 1: 17 / 17
• Subtask 2: 0 / 17
• Subtask 3: 0 / 20
• Subtask 4: 0 / 23
• Subtask 5: 0 / 23