Compilare: user.cpp: In function ‘int src(int)’: user.cpp:15:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < G[node].size(); i++) ^ user.cpp:21:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < G[node].size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:39:13: warning: unused variable ‘x’ [-Wunused-variable] int x; ^ user.cpp:36:30: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%d%d", &n, &m); ^