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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*  ****    * * ***   *   ***   ***
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*** * *  *  * **   **   *  *** * **** *  *  * *******  * * *** *           ** ****  
**  **     *******    *  * * ***  ** * *    ** * ** *    *
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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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*   * ** * **  ***  **   *  **  ** ****
    {
   ****        *      ** *  **** *** **  *    ****  * ** *
** ****  *  **  *  ** **  * ** *   **   * ***  *** *  *     
********   * *******    *    ** * **  * * ****** *   **   ** **  *   ***  **   *  *** ******** ** a prefix of %s",a,b);
***  ** **    ** * * ***** *   ** * *  **  * *  ***   * *****  ** *****  **     ** * 
* **  * **** ** ** * *** * *    **** **   *  ***  ***
*** ** * *****  * * *  ** ****  **   **** ** **   **** * *  
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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])
{
 ** **  ** *  *** * * **  * *  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__;
              ^~~~

Show more...

---

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);
         ^