04 Control Flow (Decision Making)

Program hamesha line-by-line chalta hai. Par agar humein conditions lagani ho (agar ye ho to wo karo), tab Control Flow kaam aata hai.

1. If-Else (Agar-Magar) 🤔

int marks = 40;

if (marks >= 33) {
    printf("Pass! 😎");
} else {
    printf("Fail! 😢");
}

Else If (Ladder)

if (marks >= 90) {
    printf("Grade A");
} else if (marks >= 80) {
    printf("Grade B");
} else {
    printf("Grade C");
}

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2. Switch Case (Menu Card) 📜

Jab bahut sare options hon, to switch best hai.

int day = 3;
switch(day) {
    case 1: printf("Monday"); break;
    case 2: printf("Tuesday"); break;
    case 3: printf("Wednesday"); break;
    default: printf("Invalid Day");
}

Imp: break lagana zaroori hai, warna agla case bhi chal jayega (Fallthrough).

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3. Loops (Bar-Bar Karna) 🔁

Jab same kaam baar-baar karna ho.

For Loop (Fixed times)

Jab pata ho kitni baar chalana hai.

// 0 se 4 tak print karega
for (int i = 0; i < 5; i++) {
    printf("%d ", i);
}

While Loop (Jab tak condition true hai)

Jab pata NA ho kitni baar chalana hai.

int i = 0;
while (i < 5) {
    printf("%d ", i);
    i++;
}

Do-While Loop (Kam se kam ek baar)

Condition baad me check hoti hai.

int i = 10;
do {
    printf("Ye ek baar zaroor chalega.");
} while (i < 5);

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4. Break & Continue 🛑

• break: Loop se seedha bahar nikal jao.
• continue: Current round skip karo, agle par jao.

for (int i = 0; i < 10; i++) {
    if (i == 5) continue; // 5 print nahi hoga
    if (i == 8) break;    // 8 par loop khatam
    printf("%d ", i);
}