如何按数组成员求和

// 简单数组求和
function sumArray(arr) {
  return arr.reduce((acc, val) => acc + val, 0);
}

const simpleArray = [1, 2, 3, 4, 5];
console.log(sumArray(simpleArray)); // 输出: 15

// 嵌套数组求和
function sumNestedArray(arr) {
  return arr.flat().reduce((acc, val) => acc + val, 0);
}

const nestedArray = [1, [2, 3], [4, [5]]];
console.log(sumNestedArray(nestedArray)); // 输出: 15

// 混合类型数组求和
function sumMixedArray(arr) {
  return arr.filter(item => typeof item === 'number').reduce((acc, val) => acc + val, 0);
}

const mixedArray = [1, 'a', 2, null, 3, undefined, 4, {}, 5];
console.log(sumMixedArray(mixedArray)); // 输出: 15