Compilare: user.cpp: In function ‘void solve()’: user.cpp:30:11: warning: unused variable ‘k’ [-Wunused-variable] int S, k, i; ^ user.cpp: In function ‘void read()’: user.cpp:22:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rucsac.in","r",stdin); ^ user.cpp:23:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&gm); ^ user.cpp:25:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&g[i],&c[i]); ^ user.cpp: In function ‘void print()’: user.cpp:62:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rucsac.out","w",stdout); ^