How to code for validating multiple data with similar parameter in compact way for Laravel API?

These are my API parameters

"feed_back":[
        {
            "feedId": "1",
            "rating": "1",
            "answer": "nice"
        },
        {
            "feedId": "2",
            "rating": "2",
            "answer": "nice"
        },
        {
            "feedId": "3",
            "rating": "3",
            "answer": ""
        }
    ]

For example, if I am having one of the parameters missing in the third response. so how to provide validation in this type of parameter. I can do the validation using for loop. But, I am looking for a more compact way for this type of validation.