/in/foo.c:1:1: error: unknown type name 'def'
 def Heron(a, b, c):
 ^~~
/in/foo.c: In function 'Heron':
/in/foo.c:1:19: error: expected declaration specifiers before ':' token
 def Heron(a, b, c):
                   ^
/in/foo.c:1:5: warning: type of 'a' defaults to 'int' [-Wimplicit-int]
 def Heron(a, b, c):
     ^~~~~
/in/foo.c:1:5: warning: type of 'b' defaults to 'int' [-Wimplicit-int]
/in/foo.c:1:5: warning: type of 'c' defaults to 'int' [-Wimplicit-int]
/in/foo.c:14:1: warning: control reaches end of non-void function [-Wreturn-type]
 print(Heron(x,y,z)+Heron(x,r,s)+Heron(y,r,t)+Heron(z,s,t))
 ^~~~~