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


int main()
{
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** *** *  * ** ** 
      ***   **  ",p);
* **  * ***** *  *    
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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;
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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);
         ^