View Compilation Error

0_0_19727994_27816.cpp:1:3: error: expected unqualified-id before 'while'
   while(x>='0'&&x<='9')ans=ans*10+x-'0',x=getchar();
   ^
0_0_19727994_27816.cpp:2:3: error: expected unqualified-id before 'return'
   return ans*=f;
   ^
0_0_19727994_27816.cpp:3:1: error: expected declaration before '}' token
 }
 ^