69

#include<bits/stdc++.h>
using namespace std;


int main(){
    int n, s; cin >> n >> s;
    s = s + n*(n + 1)/2 - 2;


    vector<int> a(n - 1);
    for(int i = n; i >= 2 && s; i--)
        if(2*i == s || 2*i <= s - 4)
            s -= 2*i,
            a[i - 2] = 1;


    if(s) return cout << "Impossible", 0;
    cout << 1;
    for(int i = 0; i <= n - 2; i++)
        cout << "-+"[a[i]] << i + 2;
}