AnyCompiler

while Loops

While loop tab tak chalta rehta hai jab tak uski condition true rehti hai. Iska use tab karo jab aapko pehle se pata na ho ki kitni baar loop karna hai — array par for loop ke ulat, jahan iterations ki number shuru se hi fixed hoti hai.

let count = 0;
while (count < 5) {
  console.log(count);
  count++;
}
Output
0
1
2
3
4

Woh count++ line important hai — agar bhool gaye to condition kabhi false nahi hoti, aur aapne ek infinite loop likh diya. Hamesha make sure karo ki loop ke andar kuch aisa ho jo condition ko false hone ki taraf le jaaye.

break se jaldi bahar niklna

let n = 0;
while (true) {
  if (n === 3) {
    break;
  }
  console.log(n);
  n++;
}
Output
0
1
2

break turant loop se bahar nikal jaata hai, condition kuch bhi ho. while (true) likhna common hai — ek loop jo warna kabhi nahi rukta — aur cheezein khatam karne ke liye poori tarah uske andar ek break par depend karna.

Aage: functions — code ko repeat karne ke bajaye use naam se call karne layak banana.

Practice Exercise

Ek while loop likho jo 0 se numbers print karna start kare aur jaise hi number 4 tak pahunche break se ruk jaye (isliye yeh 0, 1, 2, 3 print karega).