View Compilation Error

0_0_24125727_4776.cpp: In function 'int main()':
0_0_24125727_4776.cpp:3:7: error: 'mx' does not name a type
 const mx=1e9;
       ^
0_0_24125727_4776.cpp:4:19: error: 'mx' was not declared in this scope
     for(int i=0;i<mx;i++);
                   ^