# 【題解】Google Kick Start 2020 Round E High Buildings

```#include <iostream>
using namespace std;

int t, Case, n, a, b, c;

int main() {
cin >> t;
while (t--){
if (Case) cout << "\n";
Case++;
cout << "Case #" << Case << ":";
cin >> n >> a >> b >> c;
if (a+b-c > n){
cout << " IMPOSSIBLE";
continue;
}
if (n == 1){
cout << " " << 1;
continue;
}
if (n == 2){
if (a == 1 && b == 2) cout << " " << 2 << " " << 1;
else if (a == 2 && b == 1) cout << " " << 1 << " " << 2;
else if (a == 2 && b == 2 && c == 2) cout << " " << 1 << " " << 1;
else cout << " IMPOSSIBLE";
continue;
}
a -= c;
b -= c;
n -= a+b+c;
if (n && c == 1 && !a && !b){
cout << " IMPOSSIBLE";
continue;
}
for (int i = 0; i < a; i++){
cout << " " << 2;
}
if (n && c == 1 && a){
for (int i = 0; i < n; i++){
cout << " " << 1;
}
}
for (int i = 0; i < c-1; i++){
cout << " " << 3;
}
if (c > 1){
for (int i = 0; i < n; i++){
cout << " " << 1;
}
}
cout << " " << 3;
if (n && c == 1 && !a){
for (int i = 0; i < n; i++){
cout << " " << 1;
}
}
for (int i = 0; i < b; i++){
cout << " " << 2;
}
}
}

```