reconstruction.cpp: In function 'void mst(int, int)':
reconstruction.cpp:49:8: warning: left operand of comma operator has no effect [-Wunused-value]
   49 |  debug("mst %d id %d\n",X,id);
      |        ^~~~~~~~~~~~~~~~
reconstruction.cpp:49:27: warning: right operand of comma operator has no effect [-Wunused-value]
   49 |  debug("mst %d id %d\n",X,id);
      |                           ^~
reconstruction.cpp:61:8: warning: left operand of comma operator has no effect [-Wunused-value]
   61 |  debug("ini %d, %d %d\n",ini,E[ini].a,E[ini].b);
      |        ^~~~~~~~~~~~~~~~~
reconstruction.cpp:61:37: warning: right operand of comma operator has no effect [-Wunused-value]
   61 |  debug("ini %d, %d %d\n",ini,E[ini].a,E[ini].b);
      |                                     ^
reconstruction.cpp:61:37: warning: right operand of comma operator has no effect [-Wunused-value]
   61 |  debug("ini %d, %d %d\n",ini,E[ini].a,E[ini].b);
      |                              ~~~~~~~^
reconstruction.cpp:89:9: warning: left operand of comma operator has no effect [-Wunused-value]
   89 |   debug("+ %d %d\n",a,b);
      |         ^~~~~~~~~~~
reconstruction.cpp:89:23: warning: right operand of comma operator has no effect [-Wunused-value]
   89 |   debug("+ %d %d\n",a,b);
      |                       ^
reconstruction.cpp:78:35: warning: unused variable 'w' [-Wunused-variable]
   78 |   int a = E[get].a, b = E[get].b, w = E[get].w;
      |                                   ^
reconstruction.cpp:93:8: warning: statement has no effect [-Wunused-value]
   93 |  debug("ok\n");
      |       ~^~~~~~~
reconstruction.cpp: At global scope:
reconstruction.cpp:97:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   97 | main(){
      | ^~~~
reconstruction.cpp: In function 'int main()':
reconstruction.cpp:121:9: warning: left operand of comma operator has no effect [-Wunused-value]
  121 |   debug("ptr %d\n",ptr);
      |         ^~~~~~~~~~
reconstruction.cpp:146:9: warning: statement has no effect [-Wunused-value]
  146 |   debug("oi\n");
      |        ~^~~~~~~
reconstruction.cpp:150:11: warning: left operand of comma operator has no effect [-Wunused-value]
  150 |     debug("edge %d (%d-%d)\n",i,1+E[i].a,1+E[i].b);
      |           ^~~~~~~~~~~~~~~~~~~
reconstruction.cpp:150:40: warning: right operand of comma operator has no effect [-Wunused-value]
  150 |     debug("edge %d (%d-%d)\n",i,1+E[i].a,1+E[i].b);
      |                                        ^
reconstruction.cpp:150:34: warning: right operand of comma operator has no effect [-Wunused-value]
  150 |     debug("edge %d (%d-%d)\n",i,1+E[i].a,1+E[i].b);
      |                                 ~^~~~~~~
reconstruction.cpp:99:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   99 |  scanf("%d%d",&n,&m);
      |  ~~~~~^~~~~~~~~~~~~~
reconstruction.cpp:102:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  102 |   scanf("%d%d%d",&E[i].a,&E[i].b,&E[i].w);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
reconstruction.cpp:109:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  109 |  scanf("%d",&q);
      |  ~~~~~^~~~~~~~~
reconstruction.cpp:111:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  111 |   scanf("%d",Q+i);
      |   ~~~~~^~~~~~~~~~