Check out example codes for "vue js v-for array index". It will help you in understanding the concepts better.

Code Example 1

<option v-for="(location, index) in locations" v-bind:value="location.id" v-bind:selected="index === 0">
  {{ location.from }} - {{ location.to }}
</option>

Code Example 2

<ul>
  <li v-for="(val, index) in arr">
    <!-- Do something... -->
  </li>
</ul>

Code Example 3

<ul>
  <li v-for="(item, index) in items">
    {{ index }} - {{ item }}
  </li>
</ul>

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