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