#include <bits/stdc++.h>
using namespace std;
int t, n, m;
int main() {
cin.tie(0) -> sync_with_stdio(0);
cin >> t;
while(t--) {
cin >> n >> m;
pair<int, int> ans(-1, -1);
int cover = 0;
int sum = (n)/2+1;
for(int R=0;R<=n;R++) {
if(n-R>=sum) {
ans = max(ans, make_pair(R+m, R));
continue;
}
ans = max(ans, make_pair(min((R*((m-1)/2)/(sum-n+R)), m)+R, R));
}
cout << ans.first << '\n';
int magic = 0;
vector<string> anss;
for(int i=1;i<=ans.second;i++) {
string toprint = string(m, '+');
if(n-ans.second >= sum) {
anss.push_back(toprint);
//cout << toprint << '\n';
continue;
}
int tochange = ((m-1)/2);
for(int j=0;j<tochange;j++) {
toprint[(j+magic)%(ans.first-ans.second)] = '-';
}
magic += (m-1)/2;
anss.push_back(toprint);
//cout << toprint << '\n';
}
for(int i=ans.second+1;i<=n;i++) {
anss.push_back(string(m,'-'));
//cout << string(m, '-') << '\n';
}
for(auto &e:anss) cout << e << '\n';
}
}
