View Compilation Error

0_0_38614889_29029.cpp: In function 'int main()':
0_0_38614889_29029.cpp:13:6: error: 'b' was not declared in this scope
   if(b > a) swap(a,b);
      ^
0_0_38614889_29029.cpp:13:10: error: 'a' was not declared in this scope
   if(b > a) swap(a,b);
          ^
0_0_38614889_29029.cpp:15:9: error: 'b' was not declared in this scope
   while(b)
         ^
0_0_38614889_29029.cpp:17:7: error: 'a' was not declared in this scope
    if(a % b == 0 || a >= 2 * b) break;
       ^
0_0_38614889_29029.cpp:18:4: error: 'a' was not declared in this scope
    a = a - b;
    ^