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);
         ^