Compilare: user.cpp: In function ‘std::pair<int, int> FindnthAncestor(int, int, int)’: user.cpp:36:9: warning: unused variable ‘depth’ [-Wunused-variable] int depth=0; ^~~~~ user.cpp:68:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ user.cpp: In function ‘int main()’: user.cpp:72:24: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(IN,"%d ",&N); ^ user.cpp:76:45: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(IN,"%d %d %d %d",&a,&b,&x,&y); ^ user.cpp:103:36: warning: ‘last’ may be used uninitialized in this function [-Wmaybe-uninitialized] fprintf(OUT,"%d\n",Ans+last*2); ~~~~^~