Final Exam 2 (20%)

Question

A string p is a prefix of a string s if the leading characters of s are identical to p. For example, "abc" is a prefix of "abcde". Develop a function prefix that checks if a C string p is a prefix of another C string s.

p是s的前綴若s開頭的一段字串等於p。例如，"abc"是"abcde"的前綴。寫一個程式 判斷字串p是否字串s的前綴。

Example input 1:

abc
abcde

Example output 1:

abc is a prefix of abcde

 

Example input 2:

bc
abcde

Example output 2:

bc is not a prefix of abcde

 

Answer 1

Hidden content!
***** ** ******** ***
      *** **  *** *** *  * 

int main()
{
** *   * *  char *   * 
** **   * * *  *  int i,c=0;
 * *** **  * ** *   * **       **    *  **    * ****
*  **      ****   * * * ***** * ** ** *** *  * 
      *  *    **  * ** * ** * * * 
** * ***  **  **   {
**** * *  *  *  **  ** *  *  * * * 
*  *   ** * *  *        * *** * {
* **** *  * * ** *   *    *  **    *    ** **********   *  *       
  ** *  * *  *** *  **** *  * *   ***  * **    ***   {
*                  * ***   **  **** c=0;
    *  ** *   ***  **  * **    ** * *    *** * *  * **** }
** *****      ** *  * * ****    ***  * *  *****  else *** *   **   ** * ** * * *****  
* ****  ** * *    * *** * ** * *  **  *  ** * **   * *   **  {
 * *   * *  *  **  **   ****** *  *  *     *      *  **   *  *    **    **  c++;
 **   * ** *** * * *     ** *     *  * * **   *** * * * *   }
 *   *  **  **** **   * * ****  }
 *  **  *     *  *  
 ***  ***    *   if(c==0)
** * ** * *  **     ** * **  **  * **   * ***  * is not a prefix of  * ** *   *  *
  ****  * *   * else
 * * **   *   *  *   * *     *  ***   **  *  *  **   is a prefix of  **  ** *  
     *  ****     }
**  * *  * *  * return 0;
}

Comments

prog.c: In function 'main':
prog.c:8:11: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
   scanf("%s",&a);
           ^
prog.c:9:11: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
   scanf("%s",&b);
           ^

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

prog.c: In function 'main':
prog.c:10:6: warning: implicit declaration of function 'stlen' [-Wimplicit-function-declaration]
   if(stlen(b)>strlen(a))
      ^~~~~
/tmp/ccnE3ufV.o: In function `main':
prog.c:(.text+0x5b): undefined reference to `stlen'
collect2: error: ld returned 1 exit status

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Wrong output
Case 1: Correct output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

Answer 2

Hidden content!
** * *  ** * * 
  **  ** * *    *** ***
int main()
{
 * * * *** * *  * ap;
 * ** ***  ****   ** **    ** * *   *   || ap=a)
  ** *******   **  *****   * * **  * ****  is a prefix of abcde\n");
   *   *** *** **  ** 
**  * * ***** ***  
* *       * * * * *   * *    * *****  *  *  is not a prefix of abcde");
**    *   * *   ** *   * **  *  *   *  **    **       **  * ******* **  ****   * 0;
*  * **  **  * ** *  * * ***   * * **   * *  * **  *** * *  *         
  

Comments

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:12:12: error: expected declaration or statement at end of input
            }
            ^

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:12:12: error: expected declaration or statement at end of input
            }
            ^

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:12:12: error: expected declaration or statement at end of input
            }
            ^

Answer 3

Hidden content!
 * *     *  ** *  **  *
 * * * *   ****  *  * 

char p[1000],s[1000];
int i,pl,sl;

int test(char p[],char s[],int pl, int sl)
{
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***  ** ** * * ** * ** ***  *
  * * ***** * *   **  *  * *  ** **** *** * ******* ** *    (p[i]==s[i])
**   ** **  ** ** ** **    *** ****** ** * ** *     ****  *
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**    * **** * *  ** ****  **   * *   * ****    *   **  *** **  *
 * * *    * **  * ** ** **   *** * * * *   * * *** * ** **  * *      * **         * ** *  ** **** *   **    * *   1;
  *    ******  ***** * *  * * * ***  * * *****   ** *  *       ** *  ******  * 
   *    *    *   *** * * * **    ***   ** ****  * *
 ** *    *  * * **** **  * **** * * **  *** *  **  if(p[i]!=s[i])
   * *******   * ****   * * *   * *  ** ******  **  *** 
   * **  * *  **   ** * *     *   ** ***  *    *   *****  **** *  ***    ****  * ** 0;
**  ***  ** *  *    *  *   **  ***  **  **  **  **    *
 *  ****  *   ** ** ****    
}


int main()
{
  *   ** **   * *
 ** *   *  * 
*  **   *** * * ",p);
*  *      * **  ****** 
** **      ** ** ** **

sl=strlen(s);
pl=strlen(p);


* ****  **    * && pl<sl)
{

   * ****   *  ***   * *  **  **  *  ** * is a prefix of %s",p,s);
}else
{
printf("%s is not a prefix of %s",p,s);
}





}

Comments

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

Answer 4

Hidden content!
#include<stdio.h>
#include<string.h>
int main()
{
*  **  * *  ** *   *  * * *   a[99],b[99];
    int l,i;
*  **  ** *   * **   **   *** * *    **  *
 * *     *   *    ***  *******      * * *
*** **  *  ******* ** *    ** ****   **
** ** *   **** **        **** *  *  *    *   
    {
  **  * ***  * * ** * ** ** **   ***** ** *  ***   **  *   * **
 *** ***** ** ***   ***   ** *** * ******* ** *   
   *    ***   *** *  *** ********* ******    * ******* * **  *** * * * ** ** *   * * *  ** ** *  ** a prefix of %s",a,b);
 **   **      *  * ****** * *  **** * *    * ****  * * *    *** *  ****   **  ***  * * *
*   * *  *   *****  *   * * *** *** *  *  ** *  ***   *
 **** **** * * ****  * ***   **  **** **** *  *** *
**** *********        *  *  *** ** * * ***    **     **
*  *   * * *   **  ** * * * * **       *  * * **** *   * ** **   ** **  ***      *  * *   *** not a prefix of %s",a,b);
** * ***    **  * **  * * *   * *******     ****     *  * *  *   *  **  ** * **   *      
*  * * *** * * *  *** ***  * **  * * **  ***   *
    }


}

Comments

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

Answer 5

Hidden content!
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>

int prefix(char a[100],char b[100]);


int prefix(char a[100],char b[100])
{
*** *  *  *   *** *  **    ****  i;
* * ***   ***** * **  * *  count=0;
 * * ** ****  **  *  **** len;

****  **  *****  ****** *  ***    *

 *  *   ** ***** ******** ** **** **   *
 *           * *  * ** *** *  * 
 *** * *    *** ** *** **  **    *   *********   *  
 * **      **   ** *** ***  **  * ***   * * *     * ** **
** *     * ***** ** *         ** **   **** * ** **  * *  **   * * *** *   * *    *  *** * * *
 **  * *     *   **  *****   *** * *   *******
 *  ** ***   * * * ** ** 


*      *  * *   *   **   * * *** *   *  
  * *  **   **    * ****  **
  *  ***   ****** ****    ***** *    *    ***  * ***  ** * 1;
**  *    * *   *   * *  * * ***
* *  *  * *   ****    ** *

   return 0;
}


int main()
{
***  * **  **** ***  ** *  ** a[100];
  ** ***  * *  ****  * * ** *  ***  b[100];


    ***** ** ****** * ***  *     * *  *  *** *** * ***  ***  
*   ** ** ***  *    ******* *  *  *   ***  * *    * **  * **

     **  ** * **  * ******* * *  **  **  
***  * ***** * *  *     **  *  *     ** * 

 * **  * ** * *      *  * * *   **

 {
* * **  **   ** * **** ** **  ** *  ***   *  * **  **** **  ** *    **    is a prefix of %s",a,b);
 ** **    *  ** ** ** *** *   *
 ***** ****    * *** *** *   ***
   **   *** * ** ****   * * * 
*  *  **   **   *    ** *** **     ** ********    **** * * **  ** *  ** * * *  is not a prefix of %s",a,b);
  *    * * * ****  *   * ** * **


* *   *  **  *   *     * *** 0;
}

Comments

prog.c: In function 'main':
prog.c:45:15: warning: format '%[^
   ' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
     scanf("%[^\n]*c%",&a);
               ^
prog.c:45:20: warning: spurious trailing '%' in format [-Wformat=]
     scanf("%[^\n]*c%",&a);
                    ^
prog.c:46:15: warning: format '%[^
   ' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
     scanf("%[^\n]*c%",&b);
               ^
prog.c:46:20: warning: spurious trailing '%' in format [-Wformat=]
     scanf("%[^\n]*c%",&b);
                    ^

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

Answer 6

Hidden content!
** **  **** ** *  **** *
    **        ** ***     

int **   
{
*  * *** **        ****   *  *  ** * no idea, I ****  even do it in the  * * * *   ** *
  **       ** **    *****  ** 0;
}

Comments

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

Answer 7

Hidden content!
#include *    ** * * *  *  
#include **   *** * ** 
#include *** **  *  **  

int pref(char[],char[]);

int main(){

 * * * **  *       * ***   * p[10],s[10];
   **** ** **   **  ***  **     num;

 *  ****  * *        ** ***  *
* *   *    ** * * *  *  ** ***  
  * **** * * * * * *   *****  * **   * *      *
 *    * **    * ****     *  * * **  ***  ****   **  *

    ***** *   ***  *  ****  *  ** = pref(p,s);

 ** **   *  ****** ***  **  **
   *** ** *   * *  *   * *    * ** * **    * ** **    *  **  * * ** is a prefix of %s",p,s);
    *    * * * * ** **** * ** 
*   *** *  *     *  ***  **       * * *  * **  **     * *  is not a prefix of %s",p,s);


 return 0;
}

int pref(char p[30],char s[30]){
 *    * *    *  * *    * *  *  i;

*  * *  **   * *  *** *** *     **      *  ***********
   * * * * ***   *   ** * ******   * ****  *** *   *  *       ** ****** **********  *** **      *** * **** * 
**** *   ******** * *   * *   * *  *  * **  * ** *    ** *      * * **** * * ** ** * *****  *       is a prefix of %s",p,s);
    * ***** **   ***     **** * ****  * * * * *  *****       
   ** *  ** * ****** * **** ****     **   *  **** * *  * ***  * **   ** ** ** *****        * **** * *****  is not a prefix of %s",p,s);

* *    ** **   * ** *  ***  **

}

Comments

prog.c: In function 'main':
prog.c:12:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(p);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
prog.c:13:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(s);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/tmp/cc0tBG5r.o: In function `main':
prog.c:(.text+0x1f): warning: the `gets' function is dangerous and should not be used.

---

prog.c: In function 'main':
prog.c:10:13: error: stray '#' in program
     int num;#include <stdio.h>
             ^
prog.c:10:14: error: 'include' undeclared (first use in this function)
     int num;#include <stdio.h>
              ^~~~~~~
prog.c:10:14: note: each undeclared identifier is reported only once for each function it appears in
prog.c:10:23: error: 'stdio' undeclared (first use in this function)
     int num;#include <stdio.h>
                       ^~~~~
prog.c:14:1: error: expected expression before 'int'
 int pref(char[],char[]);
 ^~~
prog.c: In function 'main':
prog.c:23:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&p);
             ^
prog.c:24:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&s);
             ^
prog.c: In function 'main':
prog.c:51:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(p);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
prog.c:52:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(s);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~

---

prog.c: In function 'main':
prog.c:14:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&p);
             ^
prog.c:15:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&s);
             ^

Answer 8

Hidden content!
* ****  ***  *  * * 
 * * *   ** *** *     **

int main()
{
   * **  length1, ** *   c;
**  *   * a[100];
     * * b[100];
* *** d[100];

  * *  **      ** * *****     ** *  *  
 *  * * * **  ** **  **     *  *** 

    *  *** *** *  **  

 *   ** *** *** *  

     *  *** *    **
    
*  *** * * * *   *** **  **  *   is a prefix of  **  * * ****
  *    *
  **  * * *   ** 
* * ** **
**   *   *    **** * is not a prefix of * *  *  ***
****   

}

Comments

prog.c: In function 'main':
prog.c:11:10: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
  scanf("%s",&a);
          ^
prog.c:12:10: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
  scanf("%s",&b);
          ^
prog.c:24:11: warning: format '%s' expects a matching 'char *' argument [-Wformat=]
  printf("%s is not a prefix of %s,a,b");
           ^
prog.c:24:33: warning: format '%s' expects a matching 'char *' argument [-Wformat=]
  printf("%s is not a prefix of %s,a,b");
                                 ^

Answer 9

Hidden content!
 * ***    ****  *
*   ******   ** **  * 

int main()
{
 **** **** *  *   * ** * **  ** str;
 **  **  **** *****  *  i, p, s;

  * ******  *    *  ******** * * *   ** *** &p, &s);

 * *  **      * *  *  *****  (i<=0; &p; i++);
*   * **   **  *******  *  * 
    * ** ** ** ** *   ** *     * **   *  ****    **  ** &p);
  * * * *  ***     ** * *     *** ***   * * 
 * **** *      *  *   * ***
*  ** * *  * ** ***  ****

*****      * *  * *  **** 0;
}

Comments

prog.c: In function 'main':
prog.c:12:7: error: expected '(' before '{' token
     if{}
       ^
prog.c:13:12: warning: too many arguments for format [-Wformat-extra-args]
     printf("abc", &p);
            ^~~~~
prog.c:14:13: warning: format '%d' expects a matching 'int *' argument [-Wformat=]
     scanf("%d");
             ^

Answer 10

Hidden content!
   *  ****  * ****   ****
      * ** *** ** *   
int main (){
char *  **** ** 
char *  ****
   * **** **   *   **   *   **
* * ** **  *   *   ***     * * ** *
 **   ****  *  *  *  * * ***
* * *****   **   * *** **
*   ** * ****  * * ** 
  * *  *  *    is a prefix of  ***   ** ** *   
}
else{
  *** ***   **    is not a prefix of %s * ** *      * ******
}
***** 0;
}

Comments

prog.c: In function 'main':
prog.c:7:9: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
 scanf("%s",&string1);
         ^
prog.c:9:9: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
 scanf("%s",&string2);
         ^