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)
{
** * ** ****** **    *** *** * **  * * i<pl; i++)
*  *        *   ******* ***
   * * **** **   **  *   ******* *  * * *  **      ** *   *  *** (p[i]==s[i])
 * *  *   *  * * ** * **** *    ** *** ** ** *      *** 
**       **      *  * * ** **  * * *   ** *** **  * *   ***   **   ***** *  ***** * ****
**   **   * *  *   *    * *   **  **  **  ***   *  * *******  *    *   *** * *   *  *  *  
****    ** ********  *   **** ** * ** *  *  ******   *  * *  *****  ** ***   **      * * *  * * * ** **  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);
         ^