Submission #2801

#	Time	Username	Problem	Language	Result	Execution time	Memory
2801		kk1401	다각형 (GA5_polygon)	C++98	100 / 100	0 ms	1088 KiB

polygon

#include<stdio.h>

long long f(long long k)
{
    if(k==1 || k==0) return 2;
    if(k%2ll==1ll) k--;
    int kk=k/2ll;
    return kk*(kk+1ll);
}

int main()
{
    long long a,b;
    scanf("%lld%lld",&a,&b);
    printf("%lld",f(b)-f(a-1));
    return 0;
}

• Subtask 1: 60 / 60
• Subtask 2: 10 / 10
• Subtask 3: 30 / 30