#include <bits/stdc++.h>   using namespace std;   inline int read() {     register int x = 0, f = 1, ch = getchar();     while (!isdigit(ch)) {       if (ch ==  - ) f = -1;       ch = getchar();     }     while (isdigit(ch)) x = x * 10 + ch -  0 , ch = getchar();     return x * f;   }   int n;   int a[1010];   int b[1010];   int main() {     n = read();     for (int i = 1; i <= n; i++) {       a[i] = read();     }     sort(a + 1, a + n + 1);     for (int i = 1; i <= n; i++) {       if (i & 1)         printf( %d  , a[(i + 1) / 2]);       else         printf( %d  , a[n - i / 2 + 1]);     }     return 0;   }   