2017 Multi-University Training Contest 1 hdu 6043

HDU 6043

思路：找规律

AC代码：

#include "iostream"
#include "string.h"
#include "stack"
#include "queue"
#include "string"
#include "vector"
#include "set"
#include "map"
#include "algorithm"
#include "stdio.h"
#include "math.h"
#define ll long long
#define bug(x) cout<<x<<" "<<"UUUUU"<<endl;
#define mem(a) memset(a,0,sizeof(a))
#define mp(x,y) make_pair(x,y)
#define pb(x) push_back(x)
using namespace std;
const long long INF = 1e18+1LL;
const int inf = 1e9+1e8;
const int N=1e5+100;
const ll mod=1e9+7;

///1011
ll n,k,ans;
int main(){
    //ios::sync_with_stdio(false),cin.tie(0),cout.tie(0);
    int T=0;
    while(cin>>n>>k){
        if(k<=n){
            cout<<"Case #"<<++T<<": "<<k<<"\n";
            continue;
        }
        k-=n;
        ll p=k%((n-1)*2);
        if(p==0) ans=n;
        else{
            if(p>n-1) p-=n-1;
            ans=p;
        }
        cout<<"Case #"<<++T<<": "<<ans<<"\n";
    }
    return 0;
}