Compilare: user.c: In function ‘decomp’: user.c:34:9: warning: array subscript has type ‘char’ [-Wchar-subscripts] while ( isDigit[s[pos]] ) ^ user.c: In function ‘main’: user.c:63:9: warning: array subscript has type ‘char’ [-Wchar-subscripts] if ( isDigit[s[i]] ) { ^ user.c:68:13: warning: array subscript has type ‘char’ [-Wchar-subscripts] } while ( isDigit[s[i]] ); ^ user.c:71:9: warning: array subscript has type ‘char’ [-Wchar-subscripts] } else if ( isLetter[s[i]] ) ^ user.c:80:5: warning: implicit declaration of function ‘sqrt’ [-Wimplicit-function-declaration] n = sqrt( n ); ^ user.c:80:9: warning: incompatible implicit declaration of built-in function ‘sqrt’ [enabled by default] n = sqrt( n ); ^ user.c:57:10: warning: ignoring return value of ‘fread’, declared with attribute warn_unused_result [-Wunused-result] fread( s, 1, MAX_N * MAX_N + 1, fin ); ^