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import java.util.Arrays;
import java.util.Scanner;
//import java.util.concurrent.ThreadLocalRandom;
public class LCS2 {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
int n = scanner.nextInt();
int[] a = new int[n];
for (int i = 0; i < n; i++) {
a[i] = scanner.nextInt();
}
int m = scanner.nextInt();
int[] b = new int[m];
for (int i = 0; i < m; i++) {
b[i] = scanner.nextInt();
}
System.out.println(third_lcs2(a, b));
// System.out.println(alt_lcs2(a, b, n, m));
// while (true) {
//// int n = ThreadLocalRandom.current().nextInt(1, 101);
//// int m = ThreadLocalRandom.current().nextInt(1, 101);
// int n = ThreadLocalRandom.current().nextInt(1, 20);
// int m = ThreadLocalRandom.current().nextInt(1, 20);
// int[] a = new int[n];
// int[] b = new int[m];
// for (int i = 0; i < a.length; i++) {
// a[i] = ThreadLocalRandom.current().nextInt(-999999999, 1000000000);
// }
// for (int i = 0; i < b.length; i++) {
// b[i] = ThreadLocalRandom.current().nextInt(-999999999, 1000000000);
// }
// int r1 = lcs2(a, b);
// int r2 = alt_lcs2(a, b, n, m);
// if (r1 == r2)
// System.out.println("ok");
// else {
// System.out.println(Arrays.toString(a));
// System.out.println(Arrays.toString(b));
// System.out.println("Wrong answer " + r1 + " " + r2);
// break;
// }
// }
}
public static int[][] editDistance(int[] A, int[] B) {
int m = B.length;
int n = A.length;
int[][] D = new int[n + 1][m + 1];
for (int i = 0; i < n + 1; i++) {
D[i][0] = i;
}
for (int j = 0; j < m + 1; j++) {
D[0][j] = j;
}
for (int j = 1; j < m + 1; j++) {
for (int i = 1; i < n + 1; i++) {
int insertion = D[i][j - 1] + 1;
int deletion = D[i - 1][j] + 1;
int match = D[i - 1][j - 1];
int mismatch = D[i - 1][j - 1] + 1;
if (A[i - 1] == B[j - 1]) {
D[i][j] = Math.min(insertion, Math.min(deletion, match));
} else {
D[i][j] = Math.min(insertion, Math.min(deletion, mismatch));
}
}
}
return D;
}
public static int lcs2(int[] a, int[] b) {
int D[][] = editDistance(a, b);
return lcs2(a.length, b.length, D);
}
private static int lcs2(int i, int j, int[][] D) {
if (i == 0 && j == 0)
return 0;
if (i > 0 && D[i][j] == D[i - 1][j] + 1)
return lcs2(i - 1, j, D);
if (j > 0 && D[i][j] == D[i][j - 1] + 1)
return lcs2(i, j - 1, D);
else if (D[i][j] == D[i - 1][j - 1])
return 1 + lcs2(i - 1, j - 1, D);
else
return lcs2(i - 1, j - 1, D);
}
public static int alt_lcs2(int[] a, int[] b, int i, int j) {
if (i == 0 || j == 0)
return 0;
if (a[i - 1] == b[j - 1])
return 1 + alt_lcs2(a, b, i - 1, j - 1);
else
return Math.max(alt_lcs2(a, b, i, j - 1), alt_lcs2(a, b, i - 1, j));
}
public static int third_lcs2(int[] a, int[] b) {
int m = b.length;
int n = a.length;
int[][] D = new int[n + 1][m + 1];
for (int j = 1; j < m + 1; j++) {
for (int i = 1; i < n + 1; i++) {
if (a[i - 1] == b[j - 1]) {
D[i][j] = D[i - 1][j - 1] + 1;
} else {
D[i][j] = Math.max(D[i - 1][j], D[i][j - 1]);
}
}
}
return D[n][m];
}
}
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