replacing strings without using inbuild functions

 Q:replacing strings without using inbuild functions.

We are using gcc compiler and terminal to compile the code and ubuntu OS.

PROGRAM:

#include<stdio.h>

int strln1(char s1[]);

int strln2(char s2[]);

void strcpy1(char s1[],char s2[]);

int main()

{

    char s1[30],s2[30];

    int result1,result2;

    printf("Enter the string s1");

    scanf("%s",s1);

    printf("Enter the string s2");

    scanf("%s",s2);

    printf("Your string s1 is %s",s1);

    printf("\nYour string s2 is %s",s2);

    result1=strln1(s1);

    result2=strln2(s2);

    printf("\nlength of string s1 is %d\n",result1);

    printf("\nlength of string s2 is %d\n",result2);

    strcpy1(s1,s2);

}

int strln1(char s1[])

{

    int i,ln;

   

    ln=0;

    i=0;

    while(s1[i]!='\0')

    {

        i++;

        ln++;

    }

    return ln;

}

int strln2(char s2[])

{

int i,ln;

   

    ln=0;

    i=0;

    while(s2[i]!='\0')

    {

        i++;

        ln++;

    }

    return ln;

}

void strcpy1(char s1[],char s2[])

{

    int z;

    z=0;

    for(z=0;s1[z]!='\0'||s2[z]!='\0';z++)

    {

       s1[z]=s2[z];

    }

    printf("s1=%s \nand s2=%s\n",s1,s2);

       

}

OUTPUTE: