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


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