Main.cc: In function 'int main()': Main.cc:14:14: error: redeclaration of 'int b2' int a,b1,b2,b2; ^ Main.cc:14:11: error: 'int b2' previously declared here int a,b1,b2,b2; ^ Main.cc:18:2: error: 'b3' was not declared in this scope b3=a/100%10; ^