Compilare: user.cpp: In function ‘int main()’: user.cpp:47:6: warning: unused variable ‘x’ [-Wunused-variable] int x, y, c, i, px, py; ^ user.cpp:47:9: warning: unused variable ‘y’ [-Wunused-variable] int x, y, c, i, px, py; ^ user.cpp:47:12: warning: unused variable ‘c’ [-Wunused-variable] int x, y, c, i, px, py; ^ user.cpp:45:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("apm.in", "r", stdin); ^ user.cpp:46:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("apm.out", "w", stdout); ^ user.cpp:48:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n, &m); ^ user.cpp:50:65: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &(edges[i].u), &(edges[i].v), &(edges[i].c)); ^