我们需要编写一个包含数字数组的JavaScript函数。该函数应从数组中选择并返回第三高的数字。
函数的时间复杂度不得超过O(n),我们必须在单次迭代中找到数字。
const arr = [1, 5, 23, 3, 676, 4, 35, 4, 2]; const findThirdMax = (arr) => { let [first, second, third] = [-Infinity, -Infinity, -Infinity]; for (let el of arr) { if (el === first || el === second || el === third) { continue; }; if (el > first) { [first, second, third] = [el, first, second]; continue; }; if (el > second) { [second, third] = [el, second]; continue; }; if (el > third) { third = el; continue; }; }; return third !== -Infinity ? third : first; }; console.log(findThirdMax(arr));
输出结果
控制台中的输出将是-
23