View Compilation Error

0_0_34761359_30193.cpp:2:7: error: 'MOD' does not name a type
 const MOD = 1e9 + 7;
       ^
0_0_34761359_30193.cpp: In function 'int fast_power(long long int, long long int)':
0_0_34761359_30193.cpp:12:21: error: 'MOD' was not declared in this scope
         n = n * n % MOD;
                     ^