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)
{
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    *****   *****  * * **** 
* *** **** ** **        *  *  * ** ** **** *   **  * (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);
         ^