JSFiddle - React, Tailwind, and code Playground
HTML
<div id="ri-grid" class="ri-grid ri-grid-size-1 ri-shadow">
<ul>
<li><a href="#"><img src="images/medium/1.jpg" alt="Whatever works"/></a></li>
<li><a href="#"><img src="images/medium/2.jpg" alt="Anything else"/></a></li>
<!-- ... -->
</ul>
</div>
JavaScript
var vectorImagens = ["images/medium/3.jpg","images/medium/4.jpg"];//exemplo
var len = vectorImagens.length; //tamanho do vectorImagens
var imagens = $('#ri-grid ul li a img'); //os elementos img
for(var i=0; i < len; i++){ //percorre o tamanho do vectorImagens
imagens.eq(i).attr('src', vectorImagens[i]);
}