674最长连续递增序列
class Solution { public: int findLengthOfLCIS(vector<int>& nums) { stack<int> st; int ans = 0; for (auto num : nums) { if (st.empty() || st.top() < num) st.push(num); else { if (st.size() > ans) ans = st.size(); while(!st.empty()) st.pop(); st.push(num); } } if (st.size() > ans) ans = st.size(); return ans; } };