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