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);
         ^