Codeforces 1023 B.Pair of Toys (Codeforces Round #504 (rated, Div. 1 + Div. 2, based on VK Cup 2018 Fi)

B. Pair of Toys

智障题目(嘤嘤嘤~)

代码:

 1 //B
 2 #include<iostream>
 3 #include<cstdio>
 4 #include<cstring>
 5 #include<algorithm>
 6 #include<bitset>
 7 #include<cassert>
 8 #include<cctype>
 9 #include<cmath>
10 #include<cstdlib>
11 #include<ctime>
12 #include<deque>
13 #include<iomanip>
14 #include<list>
15 #include<map>
16 #include<queue>
17 #include<set>
18 #include<stack>
19 #include<vector>
20 using namespace std;
21 typedef long long ll;
22
23 const double PI=acos(-1.0);
24 const double eps=1e-6;
25 const ll mod=1e9+7;
26 const int inf=0x3f3f3f3f;
27 const int maxn=1e5+10;
28 const int maxm=100+10;
29 #define ios ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
30
31 int main()
32 {
33     ll n,m;
34     scanf("%lld%lld",&n,&m);
35     if(2*n-1<m)
36         cout<<"0"<<endl;
37     else{
38         ll ans;
39         if(n>=m){
40             if(m%2==0)
41                 ans=m/2-1;
42             else
43                 ans=m/2;
44         }
45         else{
46             ans=n-m/2;
47         }
48         cout<<ans<<endl;
49     }
50 }