Compilare: user.cpp: In function ‘int main()’: user.cpp:32:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("elimin.in", "r" ,stdin); ^ user.cpp:33:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("elimin.out", "w" ,stdout); ^ user.cpp:34:45: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%ld %ld %ld %ld", &m, &n, &l, &c); ^ user.cpp:37:35: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%ld", &a[i][j]); ^ user.cpp:31:10: warning: ‘max’ may be used uninitialized in this function [-Wmaybe-uninitialized] long max; ^