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()
{
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*   ** * * ****** 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

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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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***    ** * ***** ** ** *  ** **  * *  * **  * *  *  
*****   ** * ***  * * * **  * 
}


int main()
{
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*    *** ***** *  * * **

sl=strlen(s);
pl=strlen(p);


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{

 * ** ** *      ** **   **    **    **   ** 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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*  ***       **  * *   *  *   *       *  * **** ***    *   *
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 *  ** *  ***** *  *** *  * * **   ** **   *  **** * * ***  ** *  * * **** * *** 
 ** ** ***      ** **** *     **    *  *  ** *   * **
    }


}

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;

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

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


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