biochips.cpp: In function 'void dfs(int)':
biochips.cpp:20:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
20 | for(int i=0;i<ch[u].size();i++) {
| ~^~~~~~~~~~~~~
biochips.cpp: In function 'int main()':
biochips.cpp:26:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
26 | scanf("%d %d",&n,&m);
| ~~~~~^~~~~~~~~~~~~~~
biochips.cpp:28:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
28 | scanf("%d %d",&p[i],&x[i]);
| ~~~~~^~~~~~~~~~~~~~~~~~~~~