每瓶啤酒2元,2个空酒瓶或4个瓶盖可换1瓶啤酒。10元最多可喝多少瓶啤酒?
#include<algorithm>
#include<iostream>
using namespace std;
int dfs(int p, int g, int ans)
{
if(p < 2 && g < 4) return ans;
int ret1 = 0;
int ret2 = 0;
if(p >= 2) ret1 = dfs(p - 1, g + 1, ans + 1);
if(g >= 4) ret2 = dfs(p + 1, g - 3, ans + 1);
return max(ret1, ret2);
}
int main()
{
int n;
cin>> n;
n/=2;
int ans = dfs(n, n, n);
cout<<ans<<endl;
return 0;
}