View Compilation Error

0_0_16532311_1880.cpp: In function 'long long int gcd(long long int, long long int)':
0_0_16532311_1880.cpp:73:15: error: expected ';' before 'gcd'
     return b  gcd(b, a % b) : a;
               ^
0_0_16532311_1880.cpp:73:29: error: expected ';' before ':' token
     return b  gcd(b, a % b) : a;
                             ^