function addNumberToDuplicateIds(arr) {
  var counter = {}; // 计数器对象

  for (var i = 0; i < arr.length; i++) {
    var id = arr[i].id;

    if (!counter[id]) {
      counter[id] = 1;
    } else {
      counter[id]++;
    }

    if (counter[id] > 1) {
      arr[i].id = id + counter[id];
    }
  }

  return arr;
}

// 示例用法
var array = [
  { id: "a" },
  { id: "b" },
  { id: "a" },
  { id: "c" },
  { id: "b" }
];

var result = addNumberToDuplicateIds(array);
console.log(result);