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)
{
*  *** *   ** * **    ** *   *** i<pl; i++)
 **   *  * *  ***   * **  
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* * *     *   **  *** ***** *     * *  * **  *   ***  *** ** * * * *  *
** *****   **    ** **** ***** ***  * ***** * *  * **
* * **** *  *  *  **** *  * **  ***  ***    * **    if(p[i]!=s[i])
**  * *    **** *****  * * ** *   ******* *** ** ** *
* *** ***** *  *   **  ****  *** ****  * ******** * ****   *  **  *  **** ** * *** ** *      ** 0;
*    *   *****  *  *   * *** *** *    ***** **
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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()
{
*** * *    * ** * *   **     *     a[99],b[99];
    int l,i;
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** **         ** ** ***   *  *  **  *  *
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* * *  ***** ***** *** * *   * **   *  ** *
    {
* * * **  *  *** **   *    *     ***  *   **    **     *   ****
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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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  **   ***  ***    * * ***    *  ***  * *  **     ** **
***  *    ***** * *** ** * 


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