Submission #1628

#	Time	Username	Problem	Language	Result	Execution time	Memory
1628		gs13068	지우개 (GA4_eraser)	C++98	100 / 100	18 ms	1668 KiB

eraser

#include<cstdio>

long long a[100001];
long long x,y,z,answer;

int main()
{
int i,j,n;
scanf("%d",&n);
for(i=0;i<n;i++)
{
scanf("%d",&j);
a[j]+=j;
a[j]%=1000000007;
}
for(i=1;i<=100000;i++)
{
x+=a[i];
x%=1000000007;
y+=a[i]*a[i]%1000000007;
y%=1000000007;
z+=a[i]*a[i]%1000000007*a[i]%1000000007;
z%=1000000007;
}
answer=x*x%1000000007*x%1000000007;
answer-=3*x%1000000007*y%1000000007;
answer+=1000000007;
answer%=1000000007;
answer+=2*z%1000000007;
answer%=1000000007;
answer*=166666668;
answer%=1000000007;
printf("%lld",answer);
}

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