I have list of ages and agesGroups

I want to take each element of the list ages and search in list ageGroup the interval where it is to recover the price ,If an element is in two interval so we recover the lowest price of the list ,I want the sum of the total prices.

For example :

for age 8 I have price =50 and for 20 and 67 i have two choices 90 and 70 ,I will choose the lowest price which is 70 and then the result have to be 70 70 50 = 190 price = 190

let ages = [8, 20, 67]
let agesGroups = [{
    min: 10,
    max: 90,
    price: 90
  },
  {
    min: 10,
    max: 90,
    price: 70
  },
  {
    min: 0,
    max: 10,
    price: 50
  }
]
let price = 0
ages.forEach(a => {
  agesGroups.forEach(s => {
    if (a >= s.min && a <= s.max) {
      price = price   parseInt(s.price, 10);
    }
  })
})

console.log(price);

The result that i got

price = 140

CodePudding user response：

Sometimes using Array methods are to restrictive of what's returned and it's difficult to navigate. A for...of loop is easier to read and refactor with Array methods later.

• Define prices array to keep each best price

• Outer for...of loop to iterate ages array

  • Define inRange array to keep each price within a range

  • Inner for...of loop to iterate ranges array

    • Determine if age is within range of range.min and range.max
    • Push range.price into inRange array if age is within range

  • Push the smallest range.price of inRange into prices array

    prices.push( Math.min(...inRange));
    

• Then add all prices of price array

  prices.reduce((sum, add) => sum   add)
  

let ages=[8,20,67],ranges=[{min:10,max:90,price:90},{min:10,max:90,price:70},{min:0,max:10,price:50}];
let prices = [];

for (let age of ages) {
  let inRange = [];
  for (let range of ranges) {
    if (age >= range.min && age <= range.max) {
      inRange.push(range.price);
    }
  }
  prices.push( Math.min(...inRange));
}

let total = prices.reduce((sum, add) => sum   add);

console.log(total);
      

Refactored

let ages=[8,20,67],ranges=[{min:10,max:90,price:90},{min:10,max:90,price:70},{min:0,max:10,price:50}];

let total = ages.map(age => {
  let prices = ranges.flatMap(rng => rng.min <= age && rng.max >= age ? [rng.price] : []);
  return Math.min(...prices);
  }).reduce((sum, add) => sum   add);

console.log(total)

CodePudding user response：

Solution - by the suggestion of @Barmar - using reduce(). "result" now contains minimal prices for all the ages. You can summarize them if need:

let result = []
ages.forEach(a => {
    result.push(agesGroups.reduce((res, s) => {
        if(a >= s.min && a <= s.max) {
            if (s.price < res) { res = s.price}
        }
        return res
    }, Infinity));
});
console.log(result)