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<head>
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<title>Document</title>
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<body>
<input type="text" name="" id="" class="input">
<input type="text" name="" id="" class="input">
<input type="text" name="" id="" class="input">
<input type="text" name="" id="" class="input">
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<button class="btn">Отправить</button>
</body>
<script>
let btn = document.querySelector(".btn")
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btn.onclick = function(){
let newArray = inputs.filter(function(input){
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})
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btn.style.background = "skyblue"
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else{
btn.style.background = "tomato"
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