#include <iostream>
#include<cstdio>
using namespace std;  int main(){int n;cin>>n;int ans = 0;
//  while(n){//这也是一种好的方法
//      n = n&(n-1);
//      ++ans;
//  }while(n){if(n&1) ++ans;n>>=1;}cout<<ans<<endl;return 0;
} 

#include <iostream>
#include <algorithm>
#include<cstdio>
using namespace std;  struct node{int x;int i, j;
}a[320000];int b[1000];bool cmp(node a, node b){return a.x > b.x;
}int main(){int x, n;int c = 0;cin>>n;for(int k=2; k<=2*n; ++k){for(int kk=1; kk<k; ++kk){cin>>x;a[c].x = x;a[c].i = k;a[c++].j = kk;}}sort(a, a+c, cmp);int cnt = 0;for(int i=0; i<c; ++i){if(!b[a[i].i] && !b[a[i].j]){b[a[i].i] = a[i].j;b[a[i].j] = a[i].i;++cnt;}if(cnt == n) break;}for(int i=1; i<=2*n; ++i){if(i!=1) cout<<" ";cout<<b[i];}cout<<endl;return 0;
}

#include <iostream>
#include <algorithm>
#include<cstdio>
#include<cmath>
using namespace std;  int main(){int a, b;cin>>a>>b;if(b>a) {cout<<-1<<endl;} else {int k = a/b;if(k&1) ++k;printf("%.12lf\n", (a+b)*1.0/k);}return 0;
}

#include <iostream>
#include <algorithm>
#include<cstdio>
#include<cmath>
#define N 200010
using namespace std;  __int64 a[N];
__int64 pref[N];
__int64 suff[N];int n, k, x;int main(){scanf("%d%d%d", &n, &k, &x);long long maxN = 0;for(int i=1; i<=n; ++i)scanf("%I64d", &a[i]);long long xk = (long long)(pow((double)x, (double)k) + 0.5);for(int i=1; i<=n; ++i){pref[i] = pref[i-1] | a[i];suff[n-i+1] = suff[n-i+2] | a[n-i+1];}for(int i=1; i<=n; ++i){long long num = a[i]*xk | pref[i-1] | suff[i+1];if(maxN < num)maxN = num;}printf("%I64d\n", maxN);return 0;
}