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);
         ^