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

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