Remove vowels from strings in C++

RemoveVowels(STAR).cpp

#include <iostream>

#include <string>

using namespace std;

string usrInp;
string scan;
string newStr;
string transfer;

string target1 = "a", target2 = "A",
  target3 = "e", target4 = "E",
  target5 = "i", target6 = "I",
  target7 = "o", target8 = "O",
  target9 = "U", target10 = "U";

//Per cengage: "... a function to determine whether a character is a vowel."
string determine(string usrInp) {
  for (int i = 0; i < usrInp.length(); i++) {
    scan = usrInp[i];
    if (scan == target1) {
      cout << "'a' found at index # " << i << endl;
    }
    if (scan == target2) {
      cout << "'A' found at index # " << i << endl;
    }
    if (scan == target3) {
      cout << "'e' found at index # " << i << endl;
    }
    if (scan == target4) {
      cout << "'E' found at index # " << i << endl;
    }
    if (scan == target5) {
      cout << "'i' found at index # " << i << endl;
    }
    if (scan == target6) {
      cout << "'I' found at index # " << i << endl;
    }
    if (scan == target7) {
      cout << "'o' found at index # " << i << endl;
    }
    if (scan == target8) {
      cout << "'O' found at index # " << i << endl;
    }
    if (scan == target9) {
      cout << "'u' found at index # " << i << endl;
    }
    if (scan == target10) {
      cout << "'U' found at index # " << i << endl;
    }
  }
  return usrInp;
}

//Per cengage: "...  a function to remove all the vowels"
string removeV(string transfer) {
  for (int i = 0; i < transfer.length(); i++) {
    scan = transfer[i];
    if (scan == target1) {
      transfer.erase(i, 1);
    } //erase index location [i], exactly "1" char
    if (scan == target2) {
      transfer.erase(i, 1);
    }
    if (scan == target3) {
      transfer.erase(i, 1);
    }
    if (scan == target4) {
      transfer.erase(i, 1);
    }
    if (scan == target5) {
      transfer.erase(i, 1);
    }
    if (scan == target6) {
      transfer.erase(i, 1);
    }
    if (scan == target7) {
      transfer.erase(i, 1);
    }
    if (scan == target8) {
      transfer.erase(i, 1);
    }
    if (scan == target9) {
      transfer.erase(i, 1);
    }
    if (scan == target10) {
      transfer.erase(i, 1);
    }
  }
  newStr = transfer.substr(0, transfer.length()); // assign to newStr the erased/fully scanned previous string called "transfer"
  return newStr;
}

int main() {
  cout << "String: ";
  getline(cin, usrInp);
  transfer = determine(usrInp);
  newStr = removeV(transfer);
  cout << newStr;
}
//Using the two functions like above is highly inefficient, see below:
/*
#include <iostream>
#include <string>
#include <queue>
using namespace std;

int main() {
    string usrStr;
    getline (cin, usrStr);
    cout << endl;

for (char c : usrStr){
     if ( c != 'a' && c != 'A' &&
          c != 'e' && c != 'E' &&
          c != 'i' && c != 'I' &&
          c != 'o' && c != 'O' &&
          c != 'u' && c != 'U' ) {
          cout << "[" << c << "]";
     }
}
cout << '\n';

return 0;
}



*/