foo.c:1:9: error: expected '=', ',', ';', 'asm' or '__attribute__' before '<' token
    1 | include <iostream>
      |         ^
foo.c: In function 'main':
foo.c:4:5: error: unknown type name 'string'
    4 |     string a;
      |     ^~~~~~
foo.c:5:5: error: 'cin' undeclared (first use in this function)
    5 |     cin>>a;
      |     ^~~
foo.c:5:5: note: each undeclared identifier is reported only once for each function it appears in
foo.c:7:9: error: 'cout' undeclared (first use in this function)
    7 |         cout<<a[i];
      |         ^~~~
foo.c:7:16: error: subscripted value is neither array nor pointer nor vector
    7 |         cout<<a[i];
      |                ^

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