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])
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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;
*   *** ** *** *  * ***** *****    **   
****    *   * * * *   * * * *   *  *  *
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**    *** * * ** *  **  *  *****         
    {
**** ** * ****   ** * ****    **      *   ***  ** **** * * ***** *   
**   **  * ** *  * ** ***** *  *    ** ** ** * ** *  *****  * 
* *** *** **  ** * *  * ******  * *  *******  **   ** *  **** *  *** * *  *  *     *    ** *** 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);
         ^