Mantiqiy operatorlar

Shartlarda mantiqiy operatorlar

Mantiqiy operatorlar yordamida shartlarni birlashtirish yoki ularni teskarisiga o‘zgartirish mumkin. Ular murakkabroq qarorlar qurish uchun if, else va else if bilan birga ishlaydi.

• && (AND) - barcha shartlar rost bo‘lishi shart
• || (OR) - kamida bitta shart rost bo‘lishi shart
• ! (NOT) - shartni teskarisiga o‘zgartiradi (true → false, false → true)

AND (&&)

Ikkala shart ham rost bo‘lishi kerak bo‘lganda AND (&&) operatoridan foydalaning:

int a = 200;
int b = 33;
int c = 500;

if (a > b && c > a) {
  cout << "Both conditions are true";
}

OR (||)

Shartlardan kamida bittasi rost bo‘lishi mumkin bo‘lganda OR (||) operatoridan foydalaning:

int a = 200;
int b = 33;
int c = 500;

if (a > b || a > c) {
  cout << "At least one condition is true";
}

NOT (!)

NOT operatori (!) shartni teskarisiga o‘zgartiradi:

• Agar shart true bo‘lsa, ! uni false ga aylantiradi.
• Agar shart false bo‘lsa, ! uni true ga aylantiradi.

Bu biror narsa shunday emasligini tekshirmoqchi bo‘lganingizda foydali:

int a = 33;
int b = 200;

if (!(a > b)) {
  cout << "a is NOT greater than b";
}

Hayotiy misol

Haqiqiy dasturlarda mantiqiy operatorlar ko‘pincha kirishni nazorat qilish uchun ishlatiladi. Masalan, tizimga kirish uchun muayyan talablar mavjud:

Siz tizimga kirgan bo‘lishingiz, so‘ngra administrator bo‘lishingiz yoki yuqori xavfsizlik ruxsatiga (1- yoki 2-daraja) ega bo‘lishingiz kerak:

bool isLoggedIn = true;
bool isAdmin = false;
int securityLevel = 3; // 1 = highest

if (isLoggedIn && (isAdmin || securityLevel <= 2)) {
  cout << "Access granted.";
} else {
  cout << "Access denied.";
}

// Try changing securityLevel and isAdmin to test different outcomes:
// securityLevel 1 = Access granted
// securityLevel 2 = Access granted
// securityLevel 3 = Access denied
// securityLevel 4 = Access denied
// If isAdmin = true, access is granted.