What is a loop ?

In computer programming, loops are used to repeat a block of code.

For example, let’s say we want to show a message 100 times. Then instead of writing the print statement 100 times, we can use a loop.

Types of loops -

1.For loop

for(initialization; condition ; increment/decrement)

{ C++ statement(s); }

Example -

Output

2. Do while loop

do {
 // Code block to be executed
}
while (condition);

Example -

#include <iostream>
using namespace std;

int main() {
int i = 0;
do {
cout << i << endl;
 i++;
}
while (i < 5);
return 0;
}

Output

0

1

2

3

4

3.while loop

while(condition) { statement(s); }

Example -

#include <iostream>

using namespace std;

int main ()

{

int a = 10;

while( a < 20 )

{ cout << "value of a: " << a << endl;

a++;

}

return 0;

}

Output

value of a: 10

value of a: 11

value of a: 12

value of a: 13

value of a: 14

value of a: 15

value of a: 16

value of a: 17

value of a: 18

value of a: 19