Compilare: user.cpp: In function ‘void read_input()’: user.cpp:30:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &vertex_count); ^ user.cpp:32:40: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] int u, v; scanf("%d%d", &u, &v); ^ user.cpp: In function ‘int main()’: user.cpp:103:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(scanf("%d", &test_count); test_count > 0; test_count--) { ^