Main.cc: In function ‘int main()’: Main.cc:27:10: error: ‘s’ was not declared in this scope s++; ^ Main.cc:30:4: error: ‘s2’ was not declared in this scope s2++; ^~ Main.cc:33:5: error: ‘s’ was not declared in this scope if(s==n || s2==n){ ^ Main.cc:33:13: error: ‘s2’ was not declared in this scope if(s==n || s2==n){ ^~