var array = [
?? ?{name:'張三1',age:10},
?? ?{name:'張三2',age:40},
?? ?{name:'張三3',age:40},
?? ?{name:'張三4',age:33},
?? ?{name:'張三5',age:2},
?? ?{name:'張三6',age:2},
]

var max = Math.max.apply(Math, array.map(function(o) {
?? ?return o.age;
}))
console.log(max);// 40

var min = Math.min.apply(Math, array.map(function(o) {
?? ?return o.age;
}))
console.log(min);// 2

var max = arr[0].age;
?? ?for (var i = 1; i < arr.length; i++) {
?? ?max = max < arr[i].age ? arr[i].age : max;
}
console.log(max);// 40

var min = arr[0].age;
for (var i = 1; i < arr.length; i++) {
?? ?min = min > arr[i].age ? arr[i].age : min;
}
console.log(min);// 2

var maxAgeArr = arr.filter(item=>item.age==max);
console.log(maxAgeArr);//[{name:'張三2',age:40},{name:'張三3',age:40}]

var minAgeArr = arr.filter(item=>item.age==min);
console.log(minAgeArr);//[{name:'張三5',age:2},{name:'張三6',age:2}]

[{
  value: 1
},{
  value: 2
},{
  value: 3
}]

array.reduce(callback[, initialValue])

function callbackfn(previousValue, currentValue, currentIndex, array)

let maxValue = data.reduce((prev, cur) => {
  return prev.value > cur.value ? prev : cur
})
// maxValue = { value:3 }