string length in c

1#include <stdio.h>
2#include <string.h>
3int main()
4{
5    char a[20]="Program";
6    char b[20]={'P','r','o','g','r','a','m','\0'};
7
8    // using the %zu format specifier to print size_t
9    printf("Length of string a = %zu \n",strlen(a));
10    printf("Length of string b = %zu \n",strlen(b));
11
12    return 0;
13}

1#include <stdio.h>
2// function for string length
3int string_length(char str[])
4{
5    int i;
6    // you can use while loop
7    for( i = 0; str[i] != '\0';i++);
8    return i;
9}
10int main()
11{
12    // declaring character array
13    char your_name[20]; // you can change the maximum size of string
14    printf("Type you full Name : ");
15    // taking input from user
16    gets(your_name);
17    // using string length function
18    int length = string_length(your_name);
19    // printing string length
20    printf("\nLength of your name (%s) is : %d \n\n",your_name,length);
21
22}
23

1// include all the libraries used in the program.
2#include <stdio.h>
3#include <string.h>
4
5// Calculate Length of String Using strlen() Function
6int main() 
7{ 
8    char a[100]; int length;
9	printf("Enter a string to calculate its length\n"); gets(a);
10	length = strlen(a);
11	printf("Length of the string = %d\n", length);
12	return 0; 
13}
14
15// Calculate Length of String without Using strlen() Function
16int main() 
17{
18    char s[] = "Programming is fun";
19    int i;
20
21    for (i = 0; s[i] != '\0'; ++i);
22    
23    printf("Length of the string: %d", i);
24    return 0;
25}

1/**
2* A PROGRAM THAT RETURNS THE LENGTH OF A STRING FROM THE USER
3*/
4
5#include <stdio.h>
6
7/**
8* _strlen - takes a string and returns its length
9* @i: counter variable
10* @*s: the string entered by the user from the terminal
11* Return: Length of the string = i
12*/
13int _strlen(char *s)
14{
15        int i;
16
17        for(i = 0; s[i];)
18                i++;
19
20        return(i);
21}
22
23/**
24* main - start of this program
25* @str: string entered by user
26* Return: 0 when runs successfully
27*/
28int main()
29{
30        char str[100];
31
32        printf("Enter your string\n");
33        scanf("%s",str);
34
35        printf("%s is %i characters\n", str, _strlen(str));
36
37        return 0;
38}

1#include <stdio.h>
2#include <string.h>
3int main()
4{
5  char tab[1000];
6  int d = 0;
7
8  printf("enter the string :");
9  gets(tab);
10
11  while (tab[d] != '\0'){
12    d++;
13		}
14  for (int i=0;i<1000;i++){
15		if(tab[i]==' '){
16			d--;
17			}
18	}
19	
20  printf(" the length of the string: %d\n", d);
21
22  return 0;
23}