/in/foo.c:1:1: error: unknown type name 'def'
 def gcd(n1,n2):
 ^~~
/in/foo.c: In function 'gcd':
/in/foo.c:1:15: error: expected declaration specifiers before ':' token
 def gcd(n1,n2):
               ^
/in/foo.c:1:5: warning: type of 'n1' defaults to 'int' [-Wimplicit-int]
 def gcd(n1,n2):
     ^~~
/in/foo.c:1:5: warning: type of 'n2' defaults to 'int' [-Wimplicit-int]
/in/foo.c:7:1: warning: control reaches end of non-void function [-Wreturn-type]
 print(int(a*b/gcd(a,b)))
 ^~~~~