Compilare: user.cpp: In function ‘int main()’: user.cpp:49:42: warning: value computed is not used [-Wunused-value] for(scanf("%d%d%d%d",&n,&m,&start,&fin)>0;m;--m) ^ user.cpp:46:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("fmcm.in","r",stdin); ^ user.cpp:47:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("fmcm.out","w",stdout); ^ user.cpp:51:39: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d",&x,&y,&cap,&cost); ^