answer.code: In function ‘voi solve()’:
answer.code:80:30: error: ‘S’ was not declared in this scope
   80 |         for(auto p:Ps[i])if((S[p]=E[p].size())==2)Q.push_back(p);
      |                              ^
answer.code:84:16: error: ‘S’ was not declared in this scope
   84 |             if(S[p]!=2)continue;
      |                ^
answer.code:100:22: error: ‘S’ was not declared in this scope
  100 |                 if(--S[a]==2)Q.push_back(a);
      |                      ^
answer.code:101:22: error: ‘S’ was not declared in this scope
  101 |                 if(--S[b]==2)Q.push_back(b);
      |                      ^
answer.code:110:29: error: ‘S’ was not declared in this scope
  110 |         for(auto p:Ps[i])if(S[p]>2)ok=true;
      |                             ^
answer.code:59:10: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   59 |     scanf("%u%u",&n,&m);
      |     ~~~~~^~~~~~~~~~~~~~
answer.code:61:31: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   61 |     for(uint i=0;i<m;i++)scanf("%u%u%u",U+i,V+i,W+i),E[--U[i]].push_back(i),E[--V[i]].push_back(i),W[i]--;
      |                          ~~~~~^~~~~~~~~~~~~~~~~~~~~~
answer.code: In function ‘int main()’:
answer.code:120:17: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
  120 |     uint t;scanf("%u",&t);
      |            ~~~~~^~~~~~~~~