Searching a string inside another string

Question

I want to write a program that works like this:

1: receives string1 and string2

2: compears the length of both to see which one is smaller

3: checks if the smaller string is used inside the bigger string

now I know how to write steps 1 and 2 but I don't have any idea how to solve step 3 :/

Here is my code so far:

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
    
    
int main()
{
    printf("Please enter string 1 size and then enter a text: ");
    int size1;
    scanf("%d", &size1);
    char test1[size1];
    scanf("%s", test1);
   
    printf("Please enter string 2 size and then enter a text: ");
    int size2;
    scanf("%d", &size2);
    char test2[size2];
    scanf("%s", test2);
    
    int test1_len = strlen(test1);
    int test2_len = strlen(test2);
    
    if (test1_len < test2_len)
    {
        //searching test1 in test2
    }
    else //(test1_len >= test2_len)
    {
        //searching test2 in test1
    }
    
    return 0;
}

There are many existing questions about doing this sort of thing here. Search this site for the phrase `[c] find substring in a string`. — Ken White, Oct 08 '21 at 01:31

Shep · Accepted Answer · 2021-10-08T04:06:32.897

Applied answer from similar question: Simple way to check if a string contains another string in C? to the example provided.

Also added additional case of string lengths and content matching.

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

int main()
{
    printf("Please enter string 1 size and then enter a text: ");
    int size1;
    scanf("%d", &size1);
    char test1[size1];
    scanf("%S", test1);

    printf("Please enter string 2 size and then enter a text: ");
    int size2;
    scanf("%d", &size2);
    char test2[size2];
    scanf("%S", test2);

    int test1_len = strlen(test1);
    int test2_len = strlen(test2);

    if (test1_len < test2_len)
    {
        printf("String1 length is less than String2 length");

        if (strstr(test2, test1) != NULL) {
            printf("String1 is in String2");
        } 
        else {
            printf("String1 is not in string2");
        }
    }
    else if (test1_len > test2_len)
    {
        printf("String2 length is less than String1 length");
        
        if (strstr(test1, test2) != NULL) {
            printf("String2 is in string1");
        }
        else {
            printf("String2 is not in string1");
        }
    }
    else 
    {
        printf("String1 and String2 are same length");
        
        if (strstr(test1, test2) != NULL) {
            printf("String1 and String2 are the same");
        }
        else {
            printf("String1 and String2 are not the same");
        }
    }

    return 0;
}

It would be nice to add explanation as to why this works rather than spitting out a massive wall of code with no explanations. — Frontear, Oct 08 '21 at 01:45
can you please translate this line? "strstr(test2, test1) != NULL" this is the part I do not get — Hadi Jafari, Oct 08 '21 at 03:24
uppercase ' S ' in 'scanf("%S", test1);' is a miss type. I probably wrote it wrong by accident and didn't pay attention while copying it. if the code was complete I would fix it after I didn't get my suitable result but thanks @chux — Hadi Jafari, Oct 08 '21 at 03:37

Searching a string inside another string

1 Answers1