Compilare: user.cpp: In function ‘void Read()’: user.cpp:16:32: warning: argument to ‘sizeof’ in ‘void* memset(void*, int, size_t)’ call is the same expression as the destination; did you mean to dereference it? [-Wsizeof-pointer-memaccess] memset(a[i], 0, sizeof a[i]); ^ user.cpp:17:33: warning: argument to ‘sizeof’ in ‘void* memset(void*, int, size_t)’ call is the same expression as the destination; did you mean to dereference it? [-Wsizeof-pointer-memaccess] memset(dp[i], 0, sizeof dp[i]); ^ user.cpp:21:23: warning: converting to non-pointer type ‘int’ from NULL [-Wconversion-null] dp1[i][j] = NULL; ^