How to Swap Keys and Values in a Map in TypeScript

We can swap keys and values in a map of integers in TypeScript by iterating over the original map and inserting each key-value pair into a new map with the value as the key and the key as the value.

For example,

const originalMap = new Map<number, number>([
    [1, 10],
    [2, 20],
    [3, 30],
    [4, 40],
    [5, 50]
]);

// Declare an empty map to store the swapped key-value pairs
const swappedMap = new Map<number, number>();

// Iterate over the original map and insert each key-value pair into the new map with the value as the key and the key as the value
originalMap.forEach((value, key) => {
    swappedMap.set(value, key);
});

// Print the resulting map
console.log('Swapped map of integers:');
swappedMap.forEach((value, key) => {
    console.log(`${key}: ${value}`);
});

Swapped map of integers:
10: 1
20: 2
30: 3
40: 4
50: 5

We can swap keys and values in a map of strings in TypeScript by iterating over the original map and inserting each key-value pair into a new map with the value as the key and the key as the value.

For example,

const originalMap = new Map<string, string>([
    ['one', 'uno'],
    ['two', 'dos'],
    ['three', 'tres'],
    ['four', 'cuatro'],
    ['five', 'cinco']
]);

// Declare an empty map to store the swapped key-value pairs
const swappedMap = new Map<string, string>();

// Iterate over the original map and insert each key-value pair into the new map with the value as the key and the key as the value
originalMap.forEach((value, key) => {
    swappedMap.set(value, key);
});

// Print the resulting map
console.log('Swapped map of strings:');
swappedMap.forEach((value, key) => {
    console.log(`${key}: ${value}`);
});

Swapped map of strings:
uno: one
dos: two
tres: three
cuatro: four
cinco: five

We can swap keys and values in a map with mixed key and value types in TypeScript by iterating over the original map and inserting each key-value pair into a new map with the value as the key and the key as the value. This example demonstrates swapping keys of type number with values of type string.

For example,

const originalMap = new Map<number, string>([
    [1, 'one'],
    [2, 'two'],
    [3, 'three'],
    [4, 'four'],
    [5, 'five']
]);

// Declare an empty map to store the swapped key-value pairs
const swappedMap = new Map<string, number>();

// Iterate over the original map and insert each key-value pair into the new map with the value as the key and the key as the value
originalMap.forEach((value, key) => {
    swappedMap.set(value, key);
});

// Print the resulting map
console.log('Swapped map of mixed types:');
swappedMap.forEach((value, key) => {
    console.log(`${key}: ${value}`);
});

Swapped map of mixed types:
one: 1
two: 2
three: 3
four: 4
five: 5