Character duplicate count (substring)
import java.util.*;
//Count the number of times the specified character target is duplicated in the sentence str
public class Main {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
ArrayList<String> list = new ArrayList<String>();
//Multiple sum
int count = 0;
String target = sc.nextLine();
String str = sc.nextLine();
//Pack sentences into a list character by character.
for(int i = 1; i < str.length() + 1; i++){
list.add(str.substring(i - 1, i));
}
//Extract list in order from 0, and if it is equal to the target variable, add 1 to count
for(int i = 0; i < list.size(); i++) {
if (target.equals(list.get(i))){
count++;
}
}
System.out.println(count);
}
}
/*
//Writing shorter than substring.
public class Main {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
String s = sc.nextLine();
//split is String[]return it
//Regular expression is included in the argument
//Example:(,)It will be separated by commas.
String[] str = sc.nextLine().split("");
int count = 0;
for (String p : str) {
if (s.equals(p)) {
count++;
}
}
System.out.println(count);
}
}
*/