Java程序统计每个字符的出现
假设以下是我们的字符串-
String myStr = "thisisit";
为了计算发生次数，我们使用了HashMap。循环使用并使用containsKey（0和charAt()method，计算上述字符串中每个字符的出现次数-
HashMap <Character, Integer> hashMap = new HashMap<>();
for (int i = myStr.length() - 1; i >= 0; i--) {
if (hashMap.containsKey(myStr.charAt(i))) {
int count = hashMap.get(myStr.charAt(i));
hashMap.put(myStr.charAt(i), ++count);
} else {
hashMap.put(myStr.charAt(i),1);
}
}示例
以下是计算每个字符的出现次数的程序-
import java.util.HashMap;
public class Demo {
public static void main(String[] args) {
String myStr = "thisisit";
System.out.println("String ="+myStr);
HashMap <Character, Integer> hashMap = new HashMap<>();
for (int i = myStr.length() - 1; i >= 0; i--) {
if (hashMap.containsKey(myStr.charAt(i))) {
int count = hashMap.get(myStr.charAt(i));
hashMap.put(myStr.charAt(i), ++count);
} else {
hashMap.put(myStr.charAt(i),1);
}
}
System.out.println("Counting occurrences of each character = "+hashMap);
}
}输出结果
String =thisisit
Counting occurrences of each character = {s=2, t=2, h=1, i=3}