#include <bits/stdc++.h> using namespace std; typedef long long ll; typedef pair<int, int> pii; typedef pair<ll, ll> pll; const int MAXN = 2e4; int N, M; char S[MAXN+10]; pii A[MAXN+10]; int B[MAXN+10], C[MAXN+10]; char ans[MAXN+10]; void dfs(int now) { if(now<=N) { B[now]=0; return; } dfs(A[now].first); dfs(A[now].second); } void dfs2(int now) { if(now<=N) { C[now]=0; return; } dfs2(A[now].first); dfs2(A[now].second); } int main() { scanf("%d%d", &N, &M); scanf(" %s", S+N+1); for(int i=N+1; i<=N+M; i++) { char c1, c2; int d1, d2; scanf(" %c%d %c%d", &c1, &d1, &c2, &d2); if(c1=='c') d1+=N; if(c2=='c') d2+=N; A[i]={d1, d2}; } for(int i=N+1; i<=N+M; i++) ans[i]='?'; for(int i=1; i<=N; i++) B[i]=1; for(int i=N+1; i<=N+M; i++) if(S[i]=='0') dfs(i); for(int i=N+1; i<=N+M; i++) { B[i]=B[A[i].first]|B[A[i].second]; if(B[i]==0) ans[i]='0'; } for(int i=N+1; i<=N+M; i++) { if(B[i]==1) { for(int j=1; j<=N; j++) C[j]=B[j]; dfs2(i); bool flag=true; for(int j=N+1; j<=N+M; j++) { C[j]=C[A[j].first]|C[A[j].second]; if(S[j]=='1' && C[j]==0) flag=false; } if(!flag) ans[i]='1'; } } printf("%s\n", ans+N+1); }

ili.cpp: In function 'int main()':
ili.cpp:42:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   42 |  scanf("%d%d", &N, &M);
      |  ~~~~~^~~~~~~~~~~~~~~~
ili.cpp:43:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   43 |  scanf(" %s", S+N+1);
      |  ~~~~~^~~~~~~~~~~~~~
ili.cpp:48:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   48 |   scanf(" %c%d %c%d", &c1, &d1, &c2, &d2);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~