In function 'main':
Line 2: warning: return type of 'main' is not 'int'
In function 'func':
Line 11: error: 'n' undeclared (first use in this function)
Line 11: error: (Each undeclared identifier is reported only once
Line 11: error: for each function it appears in.)
Line 12: error: 'retrun' undeclared (first use in this function)
Line 12: error: expected ';' before 'fun'