NC_91_LONGEST_INCRE_SUBARRY NC_92_LCSII NC_93_LRU
作者：互联网
package org.example.interview.practice;
import java.util.Arrays;
/**
* @author xianzhe.ma
* @date 2021/7/24
*/
public class NC_91_LONGEST_INCRE_SUBARRY {
public static int[] LIS (int[] arr) {
// write code here
int[] dp = new int[arr.length];
int[] subset = new int[arr.length + 1];
int len = 0;
for (int i = 0; i < arr.length; i++) {
if (subset[len] < arr[i]) {
len += 1;
subset[len] = arr[i];
dp[i] = len;
} else {
int idx = Arrays.binarySearch(subset, 0, len, arr[i]);
if (idx < 0) {
idx = -(idx + 1);
}
subset[idx] = arr[i];
dp[i] = idx;
}
}
int[] res = new int[len];
for (int i = arr.length - 1; i >= 0; i--) {
if (dp[i] == len) {
res[--len] = arr[i];
}
}
return res;
}
public static void printArr(int[] arr) {
for (int i=0;i<arr.length;i++) {
System.out.print(arr[i] + " ");
}
}
public static int[] LIS2 (int[] arr) {
int length = arr.length;
int[] subSet = new int[length + 1];
int[] dp = new int[length];
int len = 0;
for (int i= 0;i < length; i++) {
if (subSet[len] < arr[i]) {
len ++;
subSet[len] = arr[i];
dp[i] = len;
} else {
int index = Arrays.binarySearch(subSet, 0,len, arr[i]);
if (index < 0) {
index = -(index + 1);
}
subSet[index] = arr[i];
dp[i] = index;//index就是长度，因为subSet下标0永远是0
}
}
int[] res = new int[len];
for (int i = arr.length - 1; i >= 0; i--) {
if (dp[i] == len) {
res[--len] = arr[i];
}
}
return res;
}
public static void main (String[] args) {
// int[] arr = {1,2,3,4,5,6,7};
// int index = Arrays.binarySearch(arr, 0, arr.length, 1);
// System.out.println(index);
int[] arr = {2,1,5,3,6,4,8,9,7};
printArr(LIS2(arr));
// int[] arr2 = {1,1,2,3,4};
// int index = Arrays.binarySearch(arr2, 0, 5, 1);
// System.out.println(index);
}
}
package org.example.interview.practice;
/**
* @author xianzhe.ma
* @date 2021/7/15
*/
public class NC_92_LCSII {
public static String LCS (String s1, String s2) {
// write code here
int len1 = s1.length();
int len2 = s2.length();
if(len1 == 0 || len2 == 0)
return "-1";
int[][] dp = new int[len1+1][len2+1];
for(int i = 0; i < len1+1; i++){
for(int j = 0; j < len2+1; j++){
//初始化行列第一个元素
if(i == 0 || j == 0){
dp[i][j] = 0;
continue;
}
if(s1.charAt(i-1) == s2.charAt(j-1)){
dp[i][j] = dp[i-1][j-1]+1;
}else{
dp[i][j] = Math.max(dp[i-1][j], dp[i][j-1]);
}
}
}
//找出一个最长的公共子序列
StringBuilder sb = new StringBuilder();
int s1L = len1, s2L = len2;
while(s1L != 0 && s2L != 0){
if (s1.charAt(s1L-1) == s2.charAt(s2L-1)){
sb.append(s1.charAt(s1L - 1));
s1L--;
s2L--;
}else{
if (dp[s1L-1][s2L] > dp[s1L][s2L-1]){
s1L--;
}else{
s2L--;
}
}
}
if(sb.length() == 0)
return "-1";
return sb.reverse().toString();
}
public static String LCSii (String s1, String s2) {
// write code here
int len1 = s1.length();
int len2 = s2.length();
if(len1 == 0 || len2 == 0)
return "-1";
int[][] dp = new int[len1+1][len2+1];
for(int i = 0; i < len1+1; i++){
for(int j = 0; j < len2+1; j++){
//初始化行列第一个元素
if(i == 0 || j == 0){
dp[i][j] = 0;
continue;
}
if(s1.charAt(i-1) == s2.charAt(j-1)){
dp[i][j] = dp[i-1][j-1]+1;
}else{
dp[i][j] = Math.max(dp[i-1][j], dp[i][j-1]);
}
}
}
//找出一个最长的公共子序列
StringBuilder sb = new StringBuilder();
int s1L = len1, s2L = len2;
while(s1L != 0 && s2L != 0){
if (s1.charAt(s1L-1) == s2.charAt(s2L-1)){
sb.append(s1.charAt(s1L - 1));
s1L--;
s2L--;
}else{
if (dp[s1L-1][s2L] > dp[s1L][s2L-1]){
s1L--;
}else{
s2L--;
}
}
}
if(sb.length() == 0)
return "-1";
return sb.reverse().toString();
}
public static void main (String[] args) {
String s1 = "1A2C3D4B56";
String s2 = "B1D23A456A";
System.out.println(LCS (s1, s2));
}
}
package org.example.interview.practice;
import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.Map;
/**
* @author xianzhe.ma
* @date 2021/11/9
*/
public class NC_93_LRU {
public int[] LRU (int[][] operators, int k) {
// write code here
ArrayList<Integer> res = new ArrayList<>();
LinkedHashMap<Integer, Integer> lru = new LinkedHashMap<Integer, Integer>() {
@Override
protected boolean removeEldestEntry(Map.Entry<Integer, Integer> eldest) {
return size() > k; // 大于限定的 lru 大小时删除最老的元素
}
};
for (int[] e : operators) {
if (e[0] == 1) {
lru.put(e[1], e[2]);
} else {
int value = -1;
if (lru.containsKey(e[1])) {
value = lru.remove(e[1]); // 删除
lru.put(e[1], value); // 重新插入，成为最新的元素
}
res.add(value);
}
}
return res.stream().mapToInt(Integer::valueOf).toArray(); // 转换为数组
}
}
标签：arr,SUBARRY,int,NC,s2L,--,INCRE,s1L,dp 来源： https://www.cnblogs.com/juniorMa/p/15882126.html