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

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   *  ** *  * ***  *
 *  * *** *  * *   * 

char p[1000],s[1000];
int i,pl,sl;

int test(char p[],char s[],int pl, int sl)
{
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*** *   **     ************  
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**     * **   ***    * * * **  **        ** *  *** *  **   ** if(p[i]!=s[i])
**    * *** * *  *  *** **  *** *   **** *****  *  *   
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****  *  * **   *     *  *    **    **  *  * **     * *  
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}


int main()
{
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*      ***** * ** *
* ****   *  *  ** * 

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()
{
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    int l,i;
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* ** **** ** *** ***     *   *  *   *** 
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*** *******  * *  **   *** ** *  * *    
    {
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**   * * *     * **  * **   ***  ** *   ** * * ** ** **  ***  *** **   * * * ****  **  *** ** *  a prefix of %s",a,b);
 *      * * **  * ** *       ***** * *** * **  *** *** ****** * **    **  *   * *  ** 
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 ** * **   * *    **  *  *      **  **  *** **  *  * * **
 **  **  * * **  * *  * *     * *** *  * * ** **    *
 *   **   * ***     ** **  * * *** *   **  * ******* ****  **      **  *** ***  **  *  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;

**** *    *  *  * ***  *** * ** *   *** 

 **  * *    ** *  *  ** *  ** ** *** * **  ***
******* *** ** **  **   * *  ** * 
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 **** *   **    ** * ** ***        ****  ** *  *
***  *  * **  *    ** *****     *   *     ** ***  *** ***    ******    **  ****  ** *   
  ********     **   ** **  * ** * * * *** ** *        
 **   *** *  *  * * ****  **


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