Loops

Requirements:
Linux Distribution
g++
any text editor

My Setup:
Debian 10
g++ version 6.3.0
pluma

Sometimes you need to repeat a couple functions or statements multiple times. For this, you would use a looping mechanism. Today i will go over 4 types of loops. Those include : while, do/while, for, for each.

While :
While loops are simple loops that will repeat until the while condition is false. You would use this specifically if you are just checking a condition before going back to the start of the loop and repeating.


int x = 5;
while(x < 10){
  //execute this code
}

Do / While :
Do-while loops are similar to while loops, however the block of code that is being looped will run atleast once.I modified the first example , and despite the fact that the while condition immediately returns false, it is still run atleast once.

int x = 15;

do{

  //execute this code

}while(x < 10);

For:
For loops are used when you need to repeat an action based on an amount of times rather then checking a condition. This is kind of similar to the differences between if/else statments to switch statements. The syntax goes: for ( initialize; check condition; increment).

int arr[20];

for(int i = 0 ; i < 20 ; i++){
 arr[i] = i;
}

For each:
For each loops are interesting. They are based off arrays , or pointers to types. They syntax is for( type x : array/pointer) . This states: For each type in the array, increment to the next.

int arr[20];

for(int i : arr){
 //do stuff with the i variable to manipulate its value in arr
}

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