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);
         ^