Compilare: main.cpp: In function 'int main()': main.cpp:36:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int k=0;k<v[j].size();++k) ~^~~~~~~~~~~~ main.cpp:47:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v[0].size();++i) ~^~~~~~~~~~~~ main.cpp:49:13: warning: unused variable 'cost' [-Wunused-variable] int cost=v[0][i].c; ^~~~ main.cpp:20:28: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d %d",&n,&m); ^ main.cpp:23:38: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d %d %d",&x,&y,&z); ^