評分結果(參考) : AC (89ms, 320KB)
#include<bits/stdc++.h>
#define int long long
using namespace std;
signed main(){
ios::sync_with_stdio(false);
cin.tie(nullptr);
int n;
while(cin >> n){
vector<int> a(n);
for(int& i : a) cin >> i;
bool rev = false;
int l=0, r=n;
for(int i=0; i<n; i++){
for(int j=l; j<r; j++){
if(rev) cout << a[n-j-1] << " ";
else cout << a[j] << " ";
}
if(rev) l++;
else r--;
rev = !rev;
cout << "\n";
}
cout << "\n";
}
return 0;
}