分类讨论，把能整除的和不能整除的分类讨论
```cpp
#include<cstdio>
using namespace std;
int n,a,b,ans=100000000,m;
int main()
{
scanf("%d",&n);
for(int i=1;i<=3;i++)
{
scanf("%d %d",&a,&b);
if(n%a==0)
{
m=n/a*b;
if(m<ans) ans=m;
}
else
{
m=int(n/a+1)*b;
if(m<ans) ans=m;
}
}
printf("%d",ans);
return 0;
}
```
by Infinity_shl @ 2017-12-31 14:56:09
满分代码
by Infinity_shl @ 2017-12-31 14:56:35
@[NOIP2018](/user/43385) 谢谢您！
by cp_cp @ 2019-11-05 08:29:13