Compilare: user.cpp: In function ‘int main()’: user.cpp:16:23: warning: suggest parentheses around comparison in operand of ‘&’ [-Wparentheses] if(a[i][j]==1&a[k][j]==1) ^ user.cpp:5:29: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("fold.in","r",stdin); ^ user.cpp:6:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("fold.out","w",stdout); ^ user.cpp:7:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&m); ^ user.cpp:10:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&a[i][j]); ^