Main.cc:2:16: error: expected identifier before ‘;’ token using namespace; ^ Main.cc:3:13: error: expected unqualified-id before ‘[’ token int a[20],b,[20]; ^ Main.cc:4:7: error: ‘inta’ was not declared in this scope int g(inta,int b); ^~~~ Main.cc:4:7: note: suggested alternative: ‘int’ int g(inta,int b); ^~~~ int Main.cc:4:12: error: expected primary-expression before ‘int’ int g(inta,int b); ^~~ Main.cc:4:17: error: expression list treated as compound expression in initializer [-fpermissive] int g(inta,int b); ^ Main.cc:5:1: error: expected unqualified-id before ‘{’ token { ^ Main.cc: In function ‘int main()’: Main.cc:14:2: error: ‘cin’ was not declared in this scope cin>>n; ^~~ Main.cc:14:2: note: suggested alternative: In file included from Main.cc:1:0: /usr/include/c++/7/iostream:60:18: note: ‘std::cin’ extern istream cin; /// Linked to standard input ^~~ Main.cc:16:23: error: invalid types ‘int[int]’ for array subscript cin>>a[c]>>s[c]>>b[c]; ^ Main.cc:20:12: error: invalid types ‘int[int]’ for array subscript n2=n2*b[i]; ^ Main.cc:22:2: error: expected primary-expression before ‘or’ token or(int i=0;i& __os) ^~~~ Main.cc:28:7: error: ‘cout’ was not declared in this scope else cout<& __os) ^~~~ Main.cc:12:16: warning: unused variable ‘d’ [-Wunused-variable] int n1=0,n2=1,d; ^