import std.stdio, std.string, std.regex, std.conv;
 

void solve() {
    int n = to!int(readln.strip);
    string s = readln.strip.split.join;

    auto r = regex(r"^(0+1+|1+0+)*$");
 
    if (s.matchFirst(r)) {
        writeln("Yes");
    } else {
        writeln("No");
    }    
}

void main() {
    int t = to!int(readln.strip);
    foreach (i; 0..t) {
        solve();
    } 
}