C Programming – Day 6 | Strings in C (Characters & Text Handling) Explained

STRINGS IN C (Characters & Text Handling) 

DAY - 6

✅ We continue your learning progress 🚀

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📍 Day-6 — Strings in C (Characters & Text Handling)

Today we will learn:

✅ What is a string?
✅ Declaring & printing strings
✅ Input methods: scanf() vs gets()
✅ String functions
✅ Task + Quiz

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✅ 1️⃣ What is a String?

📌 A string is a collection of characters ending with '\0' (NULL character)

Example:

char name[20] = "Jahid";

Memory Layout:

J | a | h | i | d | \0

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✅ 2️⃣ Input & Output Strings

✅ Using scanf()

scanf("%s", name); // stops at space

✅ Using gets() — takes full sentence

gets(name);

✅ Using puts() — prints string

puts(name);

⚠ Note: gets() is unsafe in real world, but good for learning.

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✅ 3️⃣ String Functions (from <string.h>)

Function	Meaning
strlen(str)	Count characters
strcpy(dest, src)	Copy string
strcat(str1, str2)	Join strings
strcmp(a,b)	Compare strings

Example:

#include <string.h>

char a[20] = "Hello";
char b[20] = "World";
strcat(a, b);
printf("%s", a);  // HelloWorld

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🧪 Practice Example: Count Vowels

#include <stdio.h>
#include <string.h>

int main() {
    char str[50];
    int i, count = 0;

    gets(str);

    for(i = 0; str[i] != '\0'; i++){
        char ch = str[i];
        if(ch=='a'||ch=='e'||ch=='i'||ch=='o'||ch=='u'||
           ch=='A'||ch=='E'||ch=='I'||ch=='O'||ch=='U')
           count++;
    }

    printf("Vowels: %d", count);
}

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✅ Task-6

Write a program to:

✔ Input your full name
✔ Count and print:

• Total characters

• Total vowels

Example Output:

Your Name: Jahid Hasan
Total Characters: 11
Total Vowels: 4

📌 Hint: use loop until '\0' reached
📌 Include <string.h> optional

➡ Send your code — I will fix if needed ✅

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📝 Quick Quiz — Day-6

Reply like: 1C, 2A, 3B

1️⃣ Strings in C end with:
A) space
B) tab
C) NULL \0

2️⃣ Which function joins two strings?
A) strcat()
B) strcmp()
C) strlen()

3️⃣ Which function counts characters?
A) strcpy()
B) strlen()
C) printf()

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✅ Once you finish:

➡ Day-6 Completed
➡ We proceed to Day-7 (Functions in C) 🔥

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Send your Task-6 Code and Day-6 Quiz answers when ready! 😄

✅ NEXT - DAY - 7