The loops are one of the most used structures in programming, as they allow the programmer to execute a certain block of code several times without having to repeat it manually. There are three main types of loops: while, do-while, and for.
while loop
The while loop is the simplest type of repeating loop. It executes a block of code as long as a given condition is true. The while syntax is as follows:
while (condition) {
// block of code to be executed
}
For example, the following code prints the numbers 1 through 10:
int i = 1;
while (i <= 10) {
System.out.println(i);
i++;
}
do-while loop
The do-while loop is similar to the while, but the difference is that it executes the block of code at least once, even if the condition is false. The do-while syntax is as follows:
of {
// block of code to be executed
} while (condition);
For example, the following code asks the user to enter a number between 1 and 10 and keeps asking until the number is valid:
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int number;
of {
System.out.println("Enter a number between 1 and 10:");
number = scanner.nextInt();
} while (number < 1 || number > 10);
For loop
The for loop is the most complex type of loop, but it is also the most powerful. It allows the programmer to explicitly specify the number of times the block of code will be executed. The for syntax is as follows:
for (initialization; condition; increment) {
// block of code to be executed
}
For example, the following code prints the numbers 1 through 10:
for (int i = 1; i <= 10; i++) {
System.out.println(i);
}
Loops are a powerful tool for any programmer, but it's important to use them carefully to avoid infinite loops or code that is difficult to understand. With practice and experience, any programmer can master the use of loops and make their code more efficient and readable.
