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 | 
 
 
 
 #include <cstdio>
 #include <cstring>
 #include <algorithm>
 #include <cstdlib>
 #include <string>
 #include <vector>
 using namespace std;
 
 typedef long long LL;
 const int maxn = 110;
 int sta[maxn];
 string ans[20];
 
 int main() {
 freopen("lamps.in", "r", stdin);
 freopen("lamps.out", "w", stdout);
 int n, c;
 scanf("%d%d", &n, &c);
 int x;
 while (~scanf("%d", &x) && ~x) {
 sta[x - 1] = 1;
 }
 while (~scanf("%d", &x) && ~x) {
 if (sta[x - 1] == 1) {
 puts("IMPOSSIBLE");
 return 0;
 }
 sta[x - 1] = -1;
 }
 int S = 1 << 4, cnt = 0;
 for (int i = 0; i < S; ++i) {
 int k = __builtin_popcount(i);
 if (k == 4 && (c < 4 || c & 1)) {
 continue;
 }
 if (k == 3 && (c < 3 || (c & 1) == 0)) {
 continue;
 }
 if (k == 2 && (c < 2 || (c & 1))) {
 continue;
 }
 if (k == 1 && (c & 1) == 0) {
 continue;
 }
 bool ok = true;
 for (int j = 0; j < n; ++j) {
 x = 1;
 if (i & 1) {
 x ^= 1;
 }
 if ((i & 2) && (j & 1)) {
 x ^= 1;
 }
 if ((i & 4) && (j & 1) == 0) {
 x ^= 1;
 }
 if ((i & 8) && j % 3 == 0) {
 x ^= 1;
 }
 if ((sta[j] == -1 && x == 1) || (sta[j] == 1 && x == 0)) {
 ok = false;
 }
 ans[cnt] += char('0' + x);
 }
 if (ok) {
 ++cnt;
 } else {
 ans[cnt] = "";
 }
 }
 if (!cnt) {
 puts("IMPOSSIBLE");
 }
 sort(ans, ans + cnt);
 for (int i = 0; i < cnt; ++i) {
 puts(ans[i].c_str());
 }
 return 0;
 }
 
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