Java 程序查找字符串中出现次数最少的字符

编写一个Java程序，用一个例子查找字符串中出现次数最少的字符。首先，我们声明了给定字符串长度的charFreq整型数组。接下来，我们使用toCharArray将minOccStr字符串转换为minOccArr字符数组。然后，将第一个字符指定为minchar。

第一个for循环用于为charFreq数组分配字符频率。另一个for循环用于查找字符的最小出现次数。

import java.util.Scanner;

public class MinOccurChar1 {
	private static Scanner sc;
	public static void main(String[] args) {
		String minOccStr;
		int i, min;
		
		sc= new Scanner(System.in);

		System.out.print("\nEnter String to find Minimum Char Occurrence =  ");
		minOccStr = sc.nextLine();
		
		int[] charFreq = new int[minOccStr.length()];
		char[] minOccArr = minOccStr.toCharArray();
		char minChar = minOccStr.charAt(0);
		
		for(i = 0; i < minOccArr.length; i++)
		{
			charFreq[i] = 1;
			for(int j = i + 1; j < minOccArr.length; j++) {
				if(minOccArr[i] == minOccArr[j] && minOccArr[i] != ' ' && minOccArr[i] != '0') {
					charFreq[i]++;
					minOccArr[j] = '0';
				}
			}		
		}
		min = charFreq[0];
		for(i = 0; i < charFreq.length; i++) 
		{
			if(min > charFreq[i] && charFreq[i] != '0') {
				min = charFreq[i];
				minChar = minOccArr[i];
			}
		}
		System.out.println("\nThe Minimum Occurring Character = " +  minChar);
		System.out.format("'%c' Character Occurs %d Times ", minChar, min);			
	}
}

Java Program to Find Minimum Occurring Character in a String

Java 程序查找字符串中出现次数最少的字符示例 2

import java.util.Scanner;

public class MinOccurChar2 {
	private static Scanner sc;
	public static void main(String[] args) {
		String minOccStr;
		int i, min = 0;
		int[] charFreq = new int[256];
		
		sc= new Scanner(System.in);

		System.out.print("\nEnter String to find Minimum Char Occurrence =  ");
		minOccStr = sc.nextLine();
		
		for(i = 0; i < minOccStr.length(); i++)
		{
			charFreq[minOccStr.charAt(i)]++;
		}
		for(i = 0; i < 256; i++) 
		{
			if(charFreq[i] != 0) {
				if(charFreq[min] == 0 || charFreq[i] < charFreq[min]) {
					min = i;
				}
			}
		}
		System.out.format("\nThe Minimum Occurring Character = %c",  min);
		System.out.format("\n'%c' Character Occurs %d Times ", min, charFreq[min]);	
	}
}

Enter String to find Minimum Char Occurrence =  java

The Minimum Occurring Character = j
'j' Character Occurs 1 Times

这个Java程序返回字符串中出现次数最少的字符，与上面相同。在这里，我们使用Java函数分离了逻辑。

import java.util.Scanner;

public class MinOccurChar3 {
	private static Scanner sc;
	public static void main(String[] args) {
		String minOccStr;
		
		sc= new Scanner(System.in);

		System.out.print("\nEnter String to find Minimum Char Occurrence =  ");
		minOccStr = sc.nextLine();
		
		minimumCharOccurence(minOccStr);
	}

	public static void minimumCharOccurence(String minOccStr) {
		int i, min = 0;
		int[] charFreq = new int[256];
		
		for(i = 0; i < minOccStr.length(); i++)
		{
			charFreq[minOccStr.charAt(i)]++;
		}
		for(i = 0; i < 256; i++) 
		{
			if(charFreq[i] != 0) {
				if(charFreq[min] == 0 || charFreq[i] < charFreq[min]) {
					min = i;
				}
			}
		}
		System.out.format("\nThe Minimum Occurring Character = %c",  min);
		System.out.format("\n'%c' Character Occurs %d Times ", min, charFreq[min]);			
	}
}

Enter String to find Minimum Char Occurrence =  tutorialgateway

The Minimum Occurring Character = e
'e' Character Occurs 1 Times

请参考以下字符串程序。

Java 程序查找字符串中出现次数最少的字符 示例 2

Java 程序查找字符串中出现次数最少的字符示例 2