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HTML

              
                
              
            
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CSS

              
                
              
            
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JS

              
                var myArray = [2,4,565,7,8,4]
//adds all the values in the array , from left to right
var reduceArray = _.reduce(myArray, function(acc,n){return acc+n}, 0)
//changes each value in myArray into each value * 2
var mapArray = _.map(myArray, function(val){return val* 2}) 
//filters out odd numbers 
var filterArray = _.filter(myArray, function(val){ return val % 2 == 0})
//returns the sum of the collection from right to left
var rightReduceArray = _.reduceRight(myArray, function(acc, n){return acc + n}, 0)
//returns the first even number
var findArray = _.find(myArray,function(val){ return val % 2 == 0})
//filters out the even numbers
var rejectArray = _.reject(myArray, function(val){ return val % 2 == 0})
//returns if all values are even
var allArray = _.all(myArray, function(val){ return val % 2 == 0})
//checks if a string is in the array
var anyArray = _.any(myArray, function(val){ return _.isString(val)})

//defining applicative functions 
function existy(val){ return val != undefined}
function cat(){
  
      var head = _.first(arguments)
      if(existy(head)){
          return head.concat.apply(head, _.rest(arguments))
      }else return []
}



function c(fun,col){
  return _.map(col, fun)
}

console.log(c(function(el){return el +3}, [2,3,5,6,6]))
              
            
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999px

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