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Strings in C

Find string length (without strlen())

C Program: Find string length (without strlen())

Method 1: Using gets() function

#include <stdio.h>
 
int main() {
    char str[100];
    int i = 0, length = 0;
 
    // Input string
    printf("Enter a string: ");
    gets(str); // Note: unsafe, use fgets() in practice
 
    // Calculate length manually
    while (str[i] != '\0') {
        length++;
        i++;
    }
 
    // Display length
    printf("Length of the string: %d\n", length);
 
    return 0;
}

 
INPUT :
Enter a string: ITDeveloper

OUTPUT :
Length of the string: 11

Explanation

1. A string is stored in a character array str.
2. A while loop runs through each character until it reaches the null terminator ('\0').
3. The variable length counts the number of characters.
4. Finally, the total length is printed.

C Program: Find string length (without strlen())

Method 2: Using fgets() function

#include <stdio.h>
 
int main() {
    char str[100];
    int i = 0, length = 0;
 
    printf("Enter a string: ");
    fgets(str, sizeof(str), stdin);
 
    while (str[i] != '\0' && str[i] != '\n') {
        length++;
        i++;
    }
 
    printf("Length of the string: %d\n", length);
 
    return 0;
}

 
INPUT :
Enter a string: ITDeveloper

OUTPUT :
Length of the string: 11

Explanation

1. A string is stored in a character array str.
2. A while loop runs through each character until it reaches the null terminator ('\0').
3. The variable length counts the number of characters.
4. Finally, the total length is printed.