Compilare: user.cpp: In function ‘void afis(int, int)’: user.cpp:15:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(k==x) ^ user.cpp:18:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=1;j<=x;j++) ^ user.cpp: In function ‘int main()’: user.cpp:34:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("summax.in","r",stdin); ^ user.cpp:35:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("summax.out","w",stdout); ^ user.cpp:36:36: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d",&p,&x,&st,&dr); ^ user.cpp:42:43: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&f[k][i]),g[k][i]=0; ^