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Introduction
Print an Integer (Entered by the User)Add Two IntegersMultiply two Floating Point NumbersFind ASCII value of a characterCompute Quotient and RemainderSwap Two NumbersCheck Whether a Number is Even or OddFind the Frequency of Character in a StringRemove All Whitespaces from a StringRound a Number to n Decimal PlacesDecision Making and Loop
Check Whether an Alphabet is Vowel or ConsonantFind the Largest Among Three NumbersFind all Roots of a Quadratic EquationCheck Leap YearCheck Whether a Number is Positive or NegativeCheck Whether a Character is Alphabet or NotCalculate the Sum of Natural NumbersFind Factorial of a NumberGenerate Multiplication TableDisplay Fibonacci SeriesFind GCD of two NumbersFind LCM of two NumbersDisplay Characters from A to Z using loopCount Number of Digits in an IntegerReverse a NumberCalculate the Power of a NumberCheck Whether a Number is Palindrome or NotCheck Whether a Number is Prime or NotDisplay Prime Numbers Between Two IntervalsCheck Armstrong NumberDisplay Armstrong Number Between Two IntervalsDisplay Factors of a NumberMake a Simple Calculator Using switch...caseCount the Number of Vowels and Consonants in a SentenceSort Elements in Lexicographical Order (Dictionary Order)Create Pyramid and PatternFunctions
Display Prime Numbers Between Intervals Using FunctionDisplay Armstrong Numbers Between Intervals Using FunctionCheck Whether a Number can be Expressed as Sum of Two Prime NumbersFind the Sum of Natural Numbers using RecursionFind Factorial of a Number Using RecursionFind G.C.D Using RecursionConvert Binary Number to Decimal and vice-versaConvert Octal Number to Decimal and vice-versaConvert Binary Number to Octal and vice-versaReverse a Sentence Using Recursioncalculate the power using recursionArrays
Calculate Average Using ArraysFind Largest Element in an ArrayCalculate Standard DeviationAdd Two Matrix Using Multi-dimensional ArraysMultiply to Matrix Using Multi-dimensional ArraysMultiply two Matrices by Passing Matrix to a FunctionFind Transpose of a MatrixPrint an ArrayConcatenate Two ArraysConvert Character to String and Vice-VersaCheck if An Array Contains a Given ValueCollections
Join Two ListsConvert List (ArrayList) to Array and Vice-VersaConvert Map (HashMap) to ListConvert Array to Set (HashSet) and Vice-VersaSort a Map By ValuesObject and Class
Add Two Complex Numbers by Passing Class to a FunctionCalculate Difference Between Two Time PeriodsAdvanced
Convert String to DateGet Current Date/TImeConvert Milliseconds to Minutes and SecondsAdd Two DatesGet Current Working DirectoryConvert Byte Array to HexadecimalCreate String from Contents of a FileAppend Text to an Existing FileConvert a Stack Trace to a StringConvert File to byte array and Vice-VersaConvert InputStream to StringConvert OutputStream to StringLookup enum by String valueCompare StringsSort ArrayList of Custom Objects By PropertyCheck if a String is NumericJava Program to Count the Number of Vowels and Consonants in a Sentence
To understand this example, you should have the knowledge of the following Java programming topics:
Example: Program to count vowels, consonants, digits, and spaces
class Main {
public static void main(String[] args) {
String line = "This website is aw3som3.";
int vowels = 0, consonants = 0, digits = 0, spaces = 0;
line = line.toLowerCase();
for (int i = 0; i < line.length(); ++i) {
char ch = line.charAt(i);
// check if character is any of a, e, i, o, u
if (ch == 'a' || ch == 'e' || ch == 'i' || ch == 'o' || ch == 'u') {
++vowels;
}
// check if character is in between a to z
else if ((ch >= 'a' && ch <= 'z')) {
++consonants;
}
// check if character is in between 0 to 9
else if (ch >= '0' && ch <= '9') {
++digits;
}
// check if character is a white space
else if (ch == ' ') {
++spaces;
}
}
System.out.println("Vowels: " + vowels);
System.out.println("Consonants: " + consonants);
System.out.println("Digits: " + digits);
System.out.println("White spaces: " + spaces);
}
}
Output
Vowels: 7
Consonants: 11
Digits: 2
White spaces: 3
In the above example, we’ve 4 conditions for each of the checks.
- The first
if
condition is to check whether the character is a vowel or not. - The
else if
condition followingif
is to check whether the character is a consonant or not. This condition is checked only when theif
condition is false. - The second
else if
is to check whether the character is between 0 to 9 or not. - Finally, the last condition is to check whether the character is a space character or not.
For this, we’ve lowercased the line using toLowerCase(). This is an optimization done not to check for capitalized A to Z and vowels.
We’ve used length() function to know the length of the string and charAt() to get the character at the given index (position).