View Compilation Error

0_0_17201133_5075.cpp:54:4: error: conflicting declaration 'long long int mod'
 LL mod;
    ^
0_0_17201133_5075.cpp:8:11: note: previous declaration as 'const int mod'
 const int mod=10007;
           ^
0_0_17201133_5075.cpp: In function 'int main()':
0_0_17201133_5075.cpp:56:5: error: redefinition of 'int main()'
 int main()
     ^
0_0_17201133_5075.cpp:21:5: note: 'int main()' previously defined here
 int main()
     ^
0_0_17201133_5075.cpp:62:12: error: assignment of read-only variable 'mod'
         mod=1<<i;
            ^