/in/foo.cc: In function 'void Prim()':
/in/foo.cc:24:6: warning: unused variable 'tot' [-Wunused-variable]
  int tot=0;
      ^~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:102:6: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
      if(b[1]>b[i]||b[i]>b[i-1])continue;int v=0;
      ^~
/in/foo.cc:102:41: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'if'
      if(b[1]>b[i]||b[i]>b[i-1])continue;int v=0;
                                         ^~~