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)
{
***  * *  *   *        *     *  * *  * ** i<pl; i++)
**  * ******    **  *    ** 
* *  **   * * *    * ** * **  * *  **   * *  **    * (p[i]==s[i])
**** * *  **  **** ****  **  *** *       *   *** **** *****
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* * *** *  **    ** **  ***  *** ****  **   *        * * ***   **** ** ** *  *  ** * 
*   *  *  * * *** * ****   **** ** ** ** *   *      * *   * *  * ** * *   **  **  * * *** ***** *  *  *   *   *** 1;
    *   *  * **  **     ** **** * *   * * ******** ** ******** ******   *  * *
   *   * ** ****    * ** **  *  **        ****  * 
***  ** *  *  ***** **** * ** *** ***   *   ****     *  * if(p[i]!=s[i])
  *  ******* ***  *****  * *   **  ****** * ******** *  * *  
  ** *  *******  * *    ***     **  * * **   *** * *   **   * *  **  * ** **  ** *****     ** * 0;
  * **  *** **    *  * ** **    *  ** * * **  * 
*  *  *   *  ****  * * **** *
}


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;

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

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


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