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);
         ^