Format Specifiers in C

 

💻 Format Specifiers in C (With Easy Examples)

In C (developed by Dennis Ritchie), format specifiers are used in functions like printf() and scanf() to tell the compiler:
👉 what type of data you are printing or reading

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🔹 What is a Format Specifier? 🤔

A format specifier starts with % and defines the data type of a variable

👉 Example:

printf("%d", a);

Here %d means → print an integer

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🔹 Common Format Specifiers 📊

Data Type	Specifier	Meaning
int	%d	Integer
float	%f	Decimal number
double	%lf	Double precision
char	%c	Single character
string	%s	Text/string
unsigned int	%u	Positive integer
long int	%ld	Long integer
long long int	%lld	Very large integer

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🔹 Examples of Each Specifier

🔸 1. Integer (%d)

#include <stdio.h>

int main() {
    int a = 10;
    printf("%d", a);
    return 0;
}

👉 Output: 10

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🔸 2. Float (%f)

float b = 5.5;
printf("%f", b);

👉 Output: 5.500000

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🔸 3. Double (%lf)

double pi = 3.14159;
printf("%lf", pi);

👉 Output: 3.141590

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🔸 4. Character (%c)

char ch = 'A';
printf("%c", ch);

👉 Output: A

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🔸 5. String (%s)

char name[] = "Raj";
printf("%s", name);

👉 Output: Raj

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🔸 6. Unsigned Integer (%u)

unsigned int x = 20;
printf("%u", x);

👉 Output: 20

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🔸 7. Long Integer (%ld)

long int y = 100000;
printf("%ld", y);

👉 Output: 100000

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🔸 8. Long Long Integer (%lld)

long long int z = 1234567890;
printf("%lld", z);

👉 Output: 1234567890

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🔹 Multiple Values Example 🧠

#include <stdio.h>

int main() {
    int a = 10;
    float b = 5.5;
    char c = 'A';

    printf("Value: %d %f %c", a, b, c);
    return 0;
}

👉 Output:

Value: 10 5.500000 A

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🔹 Format Specifiers in scanf() 📥

int a;
scanf("%d", &a);

👉 &a means address of variable

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🔹 Important Tips ⚠️

✔ %d → int
✔ %f → float
✔ %lf → double
✔ %c → char
✔ %s → string

❗ Wrong specifier = wrong output or error

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🔹 Final Concept 🔥

👉 Format specifier = type batata hai
👉 printf = output
👉 scanf = input

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📝 Summary

• %d → integer
• %f → float
• %lf → double
• %c → character
• %s → string