问在Javascript中根据卡片值增加/减少计数，并返回准确的计数

EN

var count = 0;

function cc(card) {
  // Only change code below this line
  switch (card) {
    case ("A"):
      --count; }
    switch (card) {
     case ("2"):
      ++count; }
    switch (card) {
    case ("3"):
      ++count; }
    switch (card) {
    case ("4"):
      ++count; }
    switch (card) {
    case ("5"):
      ++count; }
    switch (card) {
    case ("6"):
      ++count; }
    switch (card) {
    case ("7"):
      }
    switch (card) {
    case ("8"):
      }
    switch (card) {
    case ("9"):
      }
    switch (card) {
    case ("10"):
      --count; }
   switch (card) {
    case ("J"):
      --count; }
   switch (card) {
    case ("Q"):
      --count; }
    switch (card) {
     case ("K"):
      --count; }

return count;
  // Only change code above this line
 }

 // Add/remove calls to test your function.
// Note: Only the last will display
 cc(2); cc(3); cc(7); cc('K'); cc('A');