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function phoneFormat(input) {
    input = input.replace(/\D/g,'') 
    var size = input.length;
    if (size > 0) {
        input = "+91 " + input;
    }
    
    if (size > 4) {
        input = input.slice(0, 6) + "-" + input.slice(6);
    }

    if (size > 9) {
        input = input.slice(0, 10) + "-" + input.slice(10);
    }

    console.log(input.length + " and size is " + size);
    return input;
}