var lengthOfLIS = function (nums) {
    const dp = new Array(nums.length).fill(1);
    for (let i = 0; i < nums.length; i++) {
        // i与i前面的元素比较
        for (let j = 0; j < i; j++) {
            // 找比i小的元素，找到一个，就让当前序列的最长子序列长度加1
            if (nums[i] > nums[j]) {
                dp[i] = Math.max(dp[i], dp[j] + 1);
            }
        }
    }
    // 找出最大的子序列
    return Math.max(...dp);
};
复制代码

var calculate = function (s) {
    s = s.trim()
    const stack = []
    let preSign = '+', num = 0, n = s.length
    for (let i = 0; i < n; i++) {
        if (s[i] >= '0') num = num * 10 + (s[i] - '0')
        if (isNaN(Number(s[i])) || i === n - 1) {
            switch (preSign) {
                case '+':
                    stack.push(num)
                    break;

                case '-':
                    stack.push(-num)
                    break;

                case '*':
                    stack.push(stack.pop() * num)
                    break;

                default:
                    stack.push(stack.pop() / num | 0)
                    break;
            }
            preSign = s[i];
            num = 0;
        }
    }
    return stack.reduce((a, b) => { return a + b }, 0)
};