Submission #2006

#	Time	Username	Problem	Language	Result	Execution time	Memory
2006		gs13105	지우개 (GA4_eraser)	C++98	48 / 100	16 ms	1668 KiB

eraser

#include <stdio.h>
#define d 1000000007

long long arr[100001];

int main()
{
	int n,i;
	long long sum1=0,sum2=0,sum3=0,vol;
	scanf("%d",&n);
	for(i=0;i<n;i++)
	{
		scanf("%d",&arr[i]);
		sum1+=arr[i];
		sum1%=d;
		sum2+=arr[i]*arr[i];
		sum2%=d;
		sum3+=((arr[i]*arr[i])%d)*arr[i];
		sum3%=d;
	}
	vol=((((sum1*sum1)%d)*sum1)%d-sum3)%d;
	for(i=0;i<n;i++)
	{
		vol-=(3*((arr[i]*arr[i])%d)*(sum1-arr[i]))%d;
		vol+=d;
		vol%=d;
	}
	while(vol%6!=0)
		vol+=d;
	vol/=6;
	printf("%lld",vol%d);
	return 0;
}

• Subtask 1: 6 / 6
• Subtask 2: 0 / 7
• Subtask 3: 16 / 16
• Subtask 4: 0 / 17
• Subtask 5: 26 / 26
• Subtask 6: 0 / 28