View Compilation Error

0_0_29577448_25111.cpp: In function 'int main()':
0_0_29577448_25111.cpp:5:13: error: expected primary-expression before '=' token
 #define maxn=1000000000
             ^
0_0_29577448_25111.cpp:47:18: note: in expansion of macro 'maxn'
         memset(a,maxn,sizeof(a));
                  ^
0_0_29577448_25111.cpp:5:13: error: expected primary-expression before '=' token
 #define maxn=1000000000
             ^
0_0_29577448_25111.cpp:67:27: note: in expansion of macro 'maxn'
         else if(d[s[s4]]==maxn) cout<<"-1"<<endl;
                           ^