Problem
Given two promises promise1 and promise2, return a new promise. promise1 and promise2 will both resolve with a number. The returned promise should resolve with the sum of the two numbers.
Example 1:
Input:
promise1 = new Promise(resolve => setTimeout(() => resolve(2), 20)),
promise2 = new Promise(resolve => setTimeout(() => resolve(5), 60))
Output: 7
Explanation: The two input promises resolve with the values of 2 and 5 respectively. The returned promise should resolve with a value of 2 + 5 = 7. The time the returned promise resolves is not judged for this problem.
Example 2:
Input:
promise1 = new Promise(resolve => setTimeout(() => resolve(10), 50)),
promise2 = new Promise(resolve => setTimeout(() => resolve(-12), 30))
Output: -2
Explanation: The two input promises resolve with the values of 10 and -12 respectively. The returned promise should resolve with a value of 10 + -12 = -2.
Constraints:
promise1 and promise2 are promises that resolve with a number
Solution (Javascript)
/**
* @param {Promise} promise1
* @param {Promise} promise2
* @return {Promise}
*/
var addTwoPromises = async function (promise1, promise2) {
// Wait for both promises to resolve and retrieve their values
const [value1, value2] = await Promise.all([promise1, promise2]);
// Return a new promise that resolves with the sum of the values
return value1 + value2;
};
// // Example usage:
// var promise1 = new Promise(resolve => setTimeout(() => resolve(2), 20));
// var promise2 = new Promise(resolve => setTimeout(() => resolve(5), 60));
// addTwoPromises(promise1, promise2)
// .then(console.log); // Output: 7
Explain:
nope.
Complexity:
- Time complexity : O(n).
- Space complexity : O(n).