View Compilation Error

0_0_15109427_26557.cpp:4:9: error: 'a' was not declared in this scope
 int gcd(a,b) {
         ^
0_0_15109427_26557.cpp:4:11: error: 'b' was not declared in this scope
 int gcd(a,b) {
           ^
0_0_15109427_26557.cpp:4:12: error: expression list treated as compound expression in initializer [-fpermissive]
 int gcd(a,b) {
            ^
0_0_15109427_26557.cpp:4:14: error: expected ',' or ';' before '{' token
 int gcd(a,b) {
              ^