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


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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** * **  * * ** *****   ** *  ** ** *  *
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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);
         ^