Divisibility

Divisibility
Time Limit:1000MS     Memory Limit:262144KB     64bit IO Format:%I64d & %I64u
Submit Status

Description

Find the number of k-divisible numbers on the segment [a, b]. In other words you need to find the number of such integer
values x that a ≤ x ≤ b and x is divisible
by k.

Input

The only line contains three space-separated integers k, a and b (1 ≤ k ≤ 1018; - 1018 ≤ a ≤ b ≤ 1018).

Output

Print the required number.

Sample Input

Input

1 1 10

Output

10

Input

2 -4 4

Output

5

求出来在a到b所有k的倍数
不可以直接用循环会超时 直接看代码

#include<cstdio>
int main()
{
long long k,a,b;
while(~scanf("%lld %lld %lld",&k,&a,&b))
{
if(a<0&&b>0){//a和b之间有一个0需要加上
a=-a;
printf("%lld\n",a/k+b/k+1);
}
else if(a<0&&b<=0){//同为负的情况
a=-a;b=-b;
if(b%k==0)
printf("%lld\n",a/k-b/k+1);
else
printf("%lld\n",a/k-b/k);
}
else{//同为正的情况
if(a%k==0)
printf("%lld\n",b/k-a/k+1);
else
printf("%lld\n",b/k-a/k);
}
}
return 0;
}