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Intuition\n Describe your first thoughts on how to solve this problem. \n\n# Approach\n Describe your approach to solving the problem. \n\n# Complexity\n- Time 
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\n\n# Complexity\n- Time complexity:\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity:\n<!-- Add your space complexity here, e.g. $$O(n)$$ -->\n\n# Code\n```javascript []\n/**\n * @param {Array<Function>} functions\n * @return {Promise<any>}\n */\nvar promiseAll = async function(functions) {\n    return new Promise((resolve, reject) => {\n        // We know the resulting array will be the same length as functions\n        const results = new Array(functions.length);\n        let count = 0;\n        functions.forEach((fn, i) => {\n            fn()\n            .then(val => {\n                results[i] = val;\n                count++;\n                if(count === functions.length) resolve(results);\n            })\n            .catch(reason => reject(reason));\n        });\n    });\n};\n\n/**\n * const promise = promiseAll([() => new Promise(res => res(42))])\n * promise.then(console.log); // [42]\n */\n```
['JavaScript']