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

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


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()
{
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    int l,i;
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** *   **   *   *** *       *   *
*** *******     * ** **** *  **** *    * ***** * *
    {
* * ** *  **   * * *    *      *  *** * *  * **   *** * **  *
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* * * ** ***** ** ** ** ** ****** **** ****  **  ***   * * * **    ** *** **** ****  
 **   ******    * *  * **  ** *  ***   ***   * **   *** *
*** ****** ** * * *  * * *   * * ** *      * **  *
* *    *** *** *** *  * *  ****  * ***   **    *
 *  *    *  ****  ****** **** * **  *** * * * **** *  *   ******  **    ***    *  * *** ** *  *   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])
{
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*        **** *   ****  * ****    count=0;
  *  ** * * ***  *   *  ** len;

  * **  **  *   * * *  * ** *  ***

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*  ***   **  ** ** **  
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*  **    * ** *     *  * **   *  *  * * ******** **** *   *
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** ** * *    * *  *  ****   ***  ****   * * ***     
** *  * * **   **  *  **


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* *     * *   **   *    ** *   *
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*   *** * * * * **** * ***
** ***  **** *  * *   * *    **

   return 0;
}


int main()
{
***** *  *****  *** **  *  ****  a[100];
      ** *  *  * *   **  *   b[100];


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****    *  **   * **  *      *** 
***  *** *   *  **  *  **** ** ****   

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 {
  *    ****    *   **   * * ***   * ****    **   ****  *****    ** 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;

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