Compilare: user.c: In function ‘main’: user.c:33:4: warning: array subscript has type ‘char’ [-Wchar-subscripts] if (a[i] == b[j]) dp[i][j] = dp[i-1][j-1]+1; ^ user.c:33:4: warning: array subscript has type ‘char’ [-Wchar-subscripts] user.c:33:4: warning: array subscript has type ‘char’ [-Wchar-subscripts] user.c:33:4: warning: array subscript has type ‘char’ [-Wchar-subscripts] user.c:34:4: warning: array subscript has type ‘char’ [-Wchar-subscripts] else dp[i][j] = max(dp[i-1][j], dp[i][j-1]); ^ user.c:34:4: warning: array subscript has type ‘char’ [-Wchar-subscripts] user.c:34:4: warning: array subscript has type ‘char’ [-Wchar-subscripts] user.c:34:4: warning: array subscript has type ‘char’ [-Wchar-subscripts] user.c:22:9: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("cmlsc.in", "r", stdin); ^ user.c:23:9: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("cmlsc.out", "w", stdout); ^ user.c:28:7: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &m, &n); ^