Monistus

input/code.cpp:1:1: error: 'cpp' does not name a type
    1 | cpp
      | ^~~
In file included from /usr/include/c++/11/iosfwd:40,
                 from /usr/include/c++/11/ios:38,
                 from /usr/include/c++/11/ostream:38,
                 from /usr/include/c++/11/iostream:39,
                 from input/code.cpp:2:
/usr/include/c++/11/bits/postypes.h:98:11: error: 'ptrdiff_t' does not name a type
   98 |   typedef ptrdiff_t     streamsize; // Signed integral type
      |           ^~~~~~~~~
/usr/include/c++/11/bits/postypes.h:41:1: note: 'ptrdiff_t' is defined in header '<cstddef>'; did you forget to '#include <cstddef>'?
   40 | #include <cwchar> // For mbstate_t
  +++ |+#include <cstddef>
   41 | 
In file included from /usr/include/c++/11/bits/exception_ptr.h:40,
                 from /usr/include/c++/11/exception:153,
                 from /usr/include/c++/11/ios:39,
                 from /usr/include/c++/11/ostream:38,
                 from /usr/include/c++/11/iostream...

cpp
#include <iostream>
#include <string>
#include <vector>

int main() {
    std::string i;
    std::string tempstr = ".";
    while (tempstr != "") {
        int z = 0;
        tempstr = "";

        for (int f = 0; f < i.length(); ++f) {
            if (z > 0) {
                tempstr += i[f];
                z -= 1;
                if (z == 0) {
                    i = i.substr(0, f) + tempstr + i.substr(f);
                    break;
                }
            } else if (isdigit(i[f])) {
                z = int(i[f]);
                i = i.substr(0, f) + i.substr(f + 1);
            }
        }
    }

    std::cout << i;
    return 0;
}