静かで孤独な日記

のんびりたまに

AOJ 2629 Manhattan

#include<bits/stdc++.h>
#define fi first
#define se second
#define show(x) cerr<<#x<<"="<<x<<"\n"
typedef long long ll;
using namespace std;
//const ll MOD=(ll)1e9+7;
//const ll inf=(ll)1e14;
const int dy[]={1,0,-1};
const int dx[]={1,0,-1};
double d;

double check(double mid){
  double x=mid;
  double y=sqrt(d*d-x*x);
  return x+y;
}

int main(){
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.precision(10);
  cout<<fixed;
#ifdef LOCAL_DEFINE
  FILE *stream1;
  //FILE *stream2;
  stream1=freopen("in","r",stdin);
  //stream2=freopen("out","w",stdout);
  if(stream1==NULL)return 0;
  //if(stream2==NULL)return 0;
#endif
  cin>>d;
  cout<<max<double>(d*sqrt(2),(double)((int)d+1))<<endl;
#ifdef LOCAL_DEFINE
  cerr<<"Time elapsed: "<<1.0*clock()/CLOCKS_PER_SEC<<"s.\n";
  fclose(stream1);
  //fclose(stream2);
#endif
  return 0;
}

うーん、なんか勘違いしていて解けなかった。
反省