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