Submission #321628

#	Time	Username	Problem	Language	Result	Execution time	Memory
321628		Lawliet	Remittance (JOI19_remittance)	C++17	15 / 100	1 ms	384 KiB

remittance

#include <bits/stdc++.h>

using namespace std;
typedef long long int lli;

const int MAXN = 1000010;
const lli INF = 5000000000000000000LL;

int n;

lli x[MAXN];
lli diff[MAXN];
lli A[MAXN], B[MAXN];

void impossible()
{
	printf("No\n");
	exit(0);
}

void addCross(int i, lli qtd)
{
	if( i >= 62 ) impossible();

	lli p = (1LL << (i - 1));

	if( qtd > INF/p ) impossible();

	x[i] += qtd; x[n] += qtd*p;
	if( x[n] >= INF ) impossible();

	for(int j = i - 1 ; j >= 1 ; j--)
		x[j] += (1LL << (i - j - 1))*qtd;
}

int main()
{
	scanf("%d",&n);

	for(int i = 1 ; i <= n ; i++)
	{
		scanf("%lld %lld",&A[i],&B[i]);
		diff[i] = A[i] - B[i];
	}

	for(int i = 1 ; i < n ; i++)
	{
		x[i] = diff[i] + x[i - 1];

		if( x[i] < 0 ) addCross( i , -x[i] );
		if( x[i]%2 == 1 ) addCross( i , 1 );

		x[i] = x[i]/2;
	}

	lli s = diff[n] + x[n - 1];
	if( s%2 != 0 || s/2 != x[n] ) impossible();

	for(int k = 1 ; k <= 100 ; k++)
	{
		for(int i = 1 ; i <= n ; i++)
		{
			lli send = min( x[i] , A[i]/2 );

			x[i] -= send; A[i] -= 2*send;
			A[(i == n) ? 1 : i + 1] += send;
		}
	}

	for(int i = 1 ; i <= n ; i++)
		if( A[i] != B[i] ) impossible();

	printf("Yes\n");
}

Compilation message (stderr)

remittance.cpp: In function 'int main()':
remittance.cpp:38:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   38 |  scanf("%d",&n);
      |  ~~~~~^~~~~~~~~
remittance.cpp:42:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   42 |   scanf("%lld %lld",&A[i],&B[i]);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 15 / 15
• Subtask 2: 0 / 40
• Subtask 3: 0 / 45