Compilare: main.cpp: In function 'void fillVertices(int)': main.cpp:35:13: warning: unused variable 'i' [-Wunused-variable] int pos,i; ^ main.cpp: In function 'void read()': main.cpp:19:35: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&vertices,&arces); ^ main.cpp:21:32: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&from,&to); ^ main.cpp: In function 'int main()': main.cpp:67:32: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("dfs.in","r",stdin); ^ main.cpp:68:34: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("dfs.out","w",stdout); ^