foo.c: In function ‘main’:
foo.c:4:9: error: ‘cin’ undeclared (first use in this function); did you mean ‘min’?
    4 |         cin>>a>>b>>c;
      |         ^~~
      |         min
foo.c:4:9: note: each undeclared identifier is reported only once for each function it appears in
foo.c:7:25: error: ‘cout’ undeclared (first use in this function)
    7 |                         cout<<a<<"<"<<b<<"<"<<c<<endl; // 1 2 3
      |                         ^~~~
foo.c:7:50: error: ‘endl’ undeclared (first use in this function)
    7 |                         cout<<a<<"<"<<b<<"<"<<c<<endl; // 1 2 3
      |                                                  ^~~~
foo.c:3:19: warning: unused variable ‘min’ [-Wunused-variable]
    3 |         int a,b,c,min;
      |                   ^~~