use std::collections::*;
use std::io::Write;

type Map<K, V> = BTreeMap<K, V>;
type Set<T> = BTreeSet<T>;
type Deque<T> = VecDeque<T>;

fn main() {
    input! {
        n: usize,
        a: [i32; 2 * n],
    }
    let mut leave = vec![0; n + 1];
    for (i, a) in a.iter().enumerate() {
        if *a < 0 {
            leave[(-*a) as usize] = i;
        }
    }
    let mut stack = vec![vec![2 * n + 4], vec![2 * n + 5]];
    let mut memo = vec![0; n + 1];
    let mut ans = vec!['.'; n];
    let c = ['G', 'S'];
    for &a in a.iter() {
        if a > 0 {
            let r = leave[a as usize];
            if let Some(x) = (0..2)
                .filter(|&x| r < *stack[x].last().unwrap())
                .min_by_key(|&x| *stack[x].last().unwrap())
            {
                memo[a as usize] = x;
                stack[x].push(r);
                ans[a as usize - 1] = c[x];
            } else {
                println!("*");
                return;
            }
        } else {
            let x = (-a) as usize;
            assert!(stack[memo[x]].pop().unwrap() == leave[x]);
        }
    }
    let ans = ans.into_iter().collect::<String>();
    println!("{}", ans);
}

// ---------- begin input macro ----------
// reference: https://qiita.com/tanakh/items/0ba42c7ca36cd29d0ac8
#[macro_export]
macro_rules! input {
    (source = $s:expr, $($r:tt)*) => {
        let mut iter = $s.split_whitespace();
        input_inner!{iter, $($r)*}
    };
    ($($r:tt)*) => {
        let s = {
            use std::io::Read;
            let mut s = String::new();
            std::io::stdin().read_to_string(&mut s).unwrap();
            s
        };
        let mut iter = s.split_whitespace();
        input_inner!{iter, $($r)*}
    };
}

#[macro_export]
macro_rules! input_inner {
    ($iter:expr) => {};
    ($iter:expr, ) => {};
    ($iter:expr, $var:ident : $t:tt $($r:tt)*) => {
        let $var = read_value!($iter, $t);
        input_inner!{$iter $($r)*}
    };
}

#[macro_export]
macro_rules! read_value {
    ($iter:expr, ( $($t:tt),* )) => {
        ( $(read_value!($iter, $t)),* )
    };
    ($iter:expr, [ $t:tt ; $len:expr ]) => {
        (0..$len).map(|_| read_value!($iter, $t)).collect::<Vec<_>>()
    };
    ($iter:expr, chars) => {
        read_value!($iter, String).chars().collect::<Vec<char>>()
    };
    ($iter:expr, bytes) => {
        read_value!($iter, String).bytes().collect::<Vec<u8>>()
    };
    ($iter:expr, usize1) => {
        read_value!($iter, usize) - 1
    };
    ($iter:expr, $t:ty) => {
        $iter.next().unwrap().parse::<$t>().expect("Parse error")
    };
}
// ---------- end input macro ----------