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])
* ** **       **   *   **** ** ** **    ** * * ** 
* ** * *   *  *   ** *  * ** **** ** **   *   **  * * *  **** *    * *****  ******* * * *   
* *** ******       *** * *   ** * **** * *   * **  * ***  *   *  ****  * *  *   ****
****** * *****  *  ** ***  * *****   **    *** **     ** ***** *** *******   ** *****  *  **     ***  ****  *  1;
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****** *  **  *  * *** *    ** **** * ****  ****  
*    *  *   ** * * * * *   **    ***  *  *****  **  * 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);
         ^