View Compilation Error

0_0_28548334_25368.cpp:5:7: error: 'MOD' does not name a type
 const MOD = 1e9 + 7;
       ^
0_0_28548334_25368.cpp: In function 'int main()':
0_0_28548334_25368.cpp:31:12: error: 'MOD' was not declared in this scope
     ans %= MOD;
            ^
0_0_28548334_25368.cpp:33:16: error: 'MOD' was not declared in this scope
    cout << ans%MOD << endl;
                ^