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Java program to count number of digits in a string
In this article of java program, we will learn how to count the number of digits in a string?
Submitted by Jyoti Singh, on October 05, 2017
Given a string and we have to count total number of digits in it using Java.
Example:
Input string: "code2017"
Output:
Number of digits: 4
In this code we have one input:
- An int input (no. of test cases or more clearly the number of strings user wants to check (say 5 i.e user wants to check 5 strings and the program will continue for 5 inputs).
- A string input (It will be a string entered by the user which needs to be checked).
For each string we will have two outputs
The number of digits in string
Consider the program: It will take number of inputs, string and print total number of digits.
import java.util.Scanner;
public class CheckDigits {
public static void main(String[] args) {
Scanner Kb=new Scanner(System.in);
System.out.println("How man strings u want to check?");
//Take the input of no. of test cases
int t=Kb.nextInt();
//looping until the test cases are zero
while(t-->0){
//Input the string
System.out.println("Enter the string!");
String s=Kb.next();
//counter to count the number of digits in a string
int digits=0;
//looping until the string length is zero
for(int i=0;i<s.length();i++){
//isDigit is a function of Character class it checks a particular char that whether it is a digit or not
if(Character.isDigit(s.charAt(i))){
//counter digit will be incremented each time when a character will be a digit
digits++;
}
}
//prints the number of digits in a string
System.out.println(digits);
}
System.out.println();
}
}