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])
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**   * ****** *** * *          **** *  *   * * *  ***  * *  *   ******    *** * *** ** * **** ** **  * *   ****  *   1;
*   *** * **** **    ***** ***    ****  * * *  * *** * **  **  ***    *   *  *** *** * **
  * ***** *      *      * *  *  *** ****** * * * **   
* *       * ** *    * *    * * ** **** *  ** *** **  *     if(p[i]!=s[i])
   * *  *   ** * ***** **** *  **  ** ** * ** ****   ** 
*  * **   *    * *** *  * *   *  * ***  *  * * **        * ** * **  *****   * ** 0;
***** **  ** * ***  *  * * *** **     *** *  * * 
 * ** * ****** ******** *** *****
}


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