#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef long double ld;
typedef complex<ld> cd;
typedef pair<int, int> pi;
typedef pair<ll,ll> pl;
typedef pair<ld,ld> pd;
typedef vector<int> vi;
typedef vector<ld> vd;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<cd> vcd;
template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;
#define FOR(i, a, b) for (int i=a; i<(b); i++)
#define F0R(i, a) for (int i=0; i<(a); i++)
#define FORd(i,a,b) for (int i = (b)-1; i >= a; i--)
#define F0Rd(i,a) for (int i = (a)-1; i >= 0; i--)
#define sz(x) (int)(x).size()
#define mp make_pair
#define pb push_back
#define f first
#define s second
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()
const int MOD = 1000000007;
const ll INF = 1e18;
const int MX = 10001;
int n,m, status[MX];
pi pre[MX];
bitset<MX> res[2*MX], posi;
bitset<2*MX> cur;
int clas(string a) {
int x = stoi(a.substr(1,sz(a)-1));
if (a[0] == 'x') return x+m;
return x;
}
bool check(int x) {
auto POSI = posi^res[x];
FOR(i,1,n+1) cur[i+m] = POSI[i];
FOR(i,1,m+1) {
cur[i] = cur[pre[i].f]|cur[pre[i].s];
if (cur[i] == 0 && status[i] == 1) return 1;
}
return 0;
}
void input() {
ios_base::sync_with_stdio(0); cin.tie(0);
cin >> n >> m;
FOR(i,1,n+1) res[m+i][i] = 1;
FOR(i,1,m+1) {
char c; cin >> c;
if ('0' <= c && c <= '1') status[i] = c-'0';
else status[i] = -1;
}
}
int main() {
input();
FOR(i,1,m+1) {
string a,b; cin >> a >> b;
int A = clas(a), B = clas(b);
res[i] = res[A]|res[B];
pre[i] = {A,B};
if (status[i] == 0) posi |= res[i];
}
posi.flip();
FOR(i,1,m+1) res[i] &= posi;
FOR(i,1,m+1) if (status[i] == -1) {
if (res[i].count() == 0) {
status[i] = 0;
continue;
}
if (check(i)) status[i] = 1;
}
FOR(i,1,m+1) {
if (status[i] == -1) cout << "?";
else cout << status[i];
}
}
/* Look for:
* the exact constraints (multiple sets are too slow for n=10^6 :( )
* special cases (n=1?)
* overflow (ll vs int?)
* array bounds
*/
