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);
         ^