代码随想录Day52

class Solution {
public:
    int lengthOfLIS(vector<int>& nums) {
        if (nums.size() <= 1) {
            return nums.size();
        }
        vector<int> dp(nums.size(), 1);
        int result = 0;
        for (int i = 1; i < nums.size(); ++i) {
            for (int j = 0; j < i; ++j) {
                if (nums[i] > nums[j]) {
                    dp[i] = max(dp[i], dp[j] + 1);
                }
            }
            if (dp[i] > result) {
                result = dp[i];
            }
        }
        return result;
    }
};

class Solution {
public:
// dp
    int findLengthOfLCIS(vector<int>& nums) {
        if (nums.size() <= 1) {
            return nums.size();
        }
        vector<int> dp(nums.size(), 1);
        int result = 0;
        for (int i = 1; i < nums.size(); ++i) {
            if (nums[i] > nums[i - 1]) {
                dp[i] = dp[i - 1] + 1;
            }
            if (dp[i] > result) {
                result = dp[i];
            }
        }
        return result;
    }
    // 贪心算法
    int findLengthOfLCIS1(vector<int>& nums) {
        if (nums.size() == 0) {
            return 0;
        }
        int result = 1;
        int count = 1;
        for (int i = 1; i < nums.size(); ++i) {
            if (nums[i] > nums[i - 1]) {
                count++;
            } else {
                count = 1;
            }
            if (count > result) {
                result = count;
            }
        }
        return result;
        
    }
};

class Solution {
public:
    int findLength(vector<int>& nums1, vector<int>& nums2) {
        vector<vector<int>> dp(nums1.size() + 1, vector<int>(nums2.size() + 1, 0));
        int result = 0;
        for (int i = 1; i < nums1.size(); i++) {
            for (int j = 1; j < nums2.size(); j++) {
                if (nums1[i - 1] == nums2[j - 1]) {
                    dp[i][j] = dp[i - 1][j - 1] + 1;
                }
                if (dp[i][j] > result) {
                    result = dp[i][j];
                }
            }
        }
        return result;
    }

    // 一维1
    int findLength1(vector<int>& nums1, vector<int>& nums2) {
        vector<int> dp(nums2.size() + 1, 0);
        int result = 0;
        for (int i = 1; i <= nums1.size(); ++i) {
            for (int j = nums2.size(); j > 0; j--) {
                if (nums1[i - 1] == nums2[j - 1]) {
                    dp[j] = dp[j - 1] + 1;
                } else dp[j] = 0; // 注意这里不相等的时候要有赋0的操作
                if (dp[j] > result) {
                    result = dp[j];
                }
            }
        }
        return result;
    }
};