Write a C program that checks if a string (s2) is detected within another string

Question

Write a C program that checks if a string (s2) is detected within another string (s1). For example, the string “hello” (s2) is within “abcdhelloworld” (s1). The output of the program should inform the user whether the string was detected and, if detected, display the position in s1.

Note: The two strings can be declared and initialized in your program.

#define SIZE 500

Example 1:

If char s1[SIZE] = "abcdhelloworld";

char s2[SIZE] = "hello";

then (below is to be displayed by your program)

s1 is abcdhelloworld

s2 is hello

The string was detected.

hello is found at position 5 in abcdhelloworld

Example 2:

If char s1[SIZE] = "This is an example";

char s2[SIZE] = "simple";

then (below is to be displayed by your program)

s1 is This is an example

s2 is simple

The string was not detected.

Explanation / Answer

#include <stdio.h>

#include <string.h>

int main()

{

//declaration of s1 and s2

char s1[] = "abcdhelloworld";

char s2[] = "hello";

//pointers for comparsion

char *p1, *p2, *p3;

int i=0,j=0,flag=0;

p1 = s1;

p2 = s2;

for(i = 0; i<strlen(s1); i++)

{

    if(*p1 == *p2)

      {

          p3 = p1;

          for(j = 0;j<strlen(s2);j++)

          {

            if(*p3 == *p2)

           {

              p3++;p2++;

            }

            else

              break;

          }

          p2 = s2;

          if(j == strlen(s2))

          {

             flag = 1;

          printf("The string was detected.");

         // hello is found at position 5 in abcdhelloworld

            printf("%s is found at position %d in %s ",s2,i,s1);

          }

      }

    p1++;

}

if(flag==0)

{

       printf("s1 is %s",s1);

       printf("s2 is %s",s2);

       printf("The string was not detected");

}

return (0);

}

Related Questions

Navigate

• Browse (All)
• Browse W
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.