/*统计字母个数
* 方法:一个chars【100】数组里面存放随机生成的100个字母
* 一个counts[26]数组里面存放每个字母出现的次数
* 刚好,chars[i]-'a'就对应counts数组的下标,检测到那个字母了就直接++
*
* */
public class CountLettersInArray {
public static void main(String[] args) {
// TODO 自动生成的方法存根
char[] chars = createArray();
System.out.println("The lowercase letters are: ");
displayArrays(chars);
int[] counts = countLetters(chars);
System.out.println();
System.out.println(" The occurrences of each letter are:");
displayCounts(counts);
}
public static char[] createArray() {
char[] chars = new char [100];
for(int i=0;i< chars.length;i++) {
chars[i] = RandomCharacter.getRandomLowerCaseLetter(); //调用另外一个类RandomCharacter里面的getRandomLowerCaseLetter方法
}
return chars;
}
public static void displayArrays(char[] chars) { //定义字符串输出格式
for(int i=0;i<chars.length;i++) {
if((i+1)%20 == 0)
System.out.println(chars[i]);
else
System.out.print(chars[i]);
}
}
public static int[] countLetters(char[] chars) {
int[] counts = new int[26];
for(int i=0;i<chars.length;i++) {
counts[chars[i]-'a']++; //counts数组用来记录对应字母出现的次数
}
return counts;
}
public static void displayCounts(int[] counts) { //输出
for(int i = 0 ; i < counts.length ; i++) {
if((i+1)%10 == 0)
System.out.println(counts[i]+"-"+(char)(i+'a')+" ");
else
System.out.print(counts[i]+"-"+(char)(i+'a')+" ");
}
}
}
class RandomCharacter { //生成随机字符串的类
public static char getRandomLowerCaseLetter() {
return getRandomCharacter('a','z');
}
public static char getRandomCharacter(char ch1,char ch2) {
return (char)(ch1 + Math.random()*(ch2 - ch1 + 1));
}
}
统计字母出现次数
猜你喜欢
转载自blog.csdn.net/alike_meng/article/details/82926951
今日推荐
周排行