Compilare: user.cpp: In function ‘int main()’: user.cpp:10:18: warning: unused variable ‘l’ [-Wunused-variable] int n,nr,i,j,l,c,maxx=-1000000000; ^ user.cpp:10:20: warning: unused variable ‘c’ [-Wunused-variable] int n,nr,i,j,l,c,maxx=-1000000000; ^ user.cpp:8:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] { freopen("sotron.in", "r",stdin); ^ user.cpp:9:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("sotron.out", "w",stdout); ^ user.cpp:11:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:24:36: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &mat[i][j]); ^