我需要打印每个字母在文本文件中出现的总次数。关于如何循环这个有什么想法吗?我已经掌握了基础知识。不确定我是否正确使用了数组。另外,我该如何打印它?
示例文本文件:
你好,我叫扎卡里。我以给人们拍 X 光片为生。
期望的输出:
字母 - 文件中的频率:
a - 7
b - 0
c - 1
d - 1
e - 4
f - 1
g - 2
小时 - 3
我 - 6
j - 0
k - 1
l - 4
米 - 2
n - 3
o - 4
p - 2
q - 0
r - 2
s - 3
t - 2
u - 0
v - 1
w - 1
x - 1
y - 3
z - 1
/*
* program that reads in a text file and counts the frequency of each letter
* displays the frequencies in descending order
*/
import java.util.*; //needed for Scanner
import java.io.*; //needed for File related classes
public class LetterCounter {
public static void main(String args[]) throws IOException{
Scanner keyboard = new Scanner(System.in); //Scanner to read in file name
System.out.println("Enter the name of the text file to read:");
String filename = keyboard.next();
//This String has all the letters of the alphabet
//You can use it to "look up" a character using alphabet.indexOf(...) to see what letter it is
//0 would indicate 'a', 1 for 'b', and so on. -1 would mean the character is not a letter
String alphabet = "abcdefghijklmnopqrstuvwxyz";
//TODO: create a way to keep track of the letter counts
//I recommend an array of 26 int values, one for each letter, so 0 would be for 'a', 1 for 'b', etc.
int[] myArray = new int[26];
Scanner fileScan = new Scanner(new File(filename)); //another Scanner to open and read the file
//loop to read file line-by-line
while (fileScan.hasNext()) { //this will continue to the end of the file
String line = fileScan.nextLine(); //get the next line of text and store it in a temporary String
line = line.toLowerCase( ); // convert to lowercase
//TODO: count the letters in the current line
for (int i=0; i<line.length(); i++) {
myArray[line.charAt(i) - 'a']++;
}
}
fileScan.close(); //done with file reading...close the Scanner so the file is "closed"
//print out frequencies
System.out.println("Letters - Frequencies in file:");
//TODO: print out all the letter counts
}
}
最佳答案
实际上,这与存储时正好相反
for (int i = 0; i < myArray.length; i++) {
System.out.printf("%c has %d%n", i + 'a', myArray[i]);
}
您还需要检查输入字符是否为 alpha
if (Character.isAlphabetic(line.charAt(i))) {
myArray[line.charAt(i) - 'a']++;
}
这段代码应该被替换
for (int i=0; i<line.length(); i++) {
myArray[line.charAt(i) - 'a']++;
}
关于java - 计算并打印文本文件中每个字母的出现次数,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/58810181/