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

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

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

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