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