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