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)
{
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 **   ** **  *  *** *    
* *******  * **  * ** *** * *   ** *  ***  * **** (p[i]==s[i])
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*  * * * **  ***** *  *  **            ***   ** *** **  *** * *  * ***    ***   
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*   ** * **  **** ******  *      ** * *  ** **   *  ** ***  * ********   *  *  ***  *****  *** ** * *  *** *** 1;
**  *  ****  *** *** ***      *** **  ** *  * *** * **   * * ****  * *** ** * * ** *   *
  ***** **** ***  ** ** * ********     * ****  *     ***  * 
  ** * * **   *** *   *  **  ***  ** ***  **  * * ***  *   if(p[i]!=s[i])
* **** ***** ***    ***  * *** *  **  **** **  *   * *   * **
* **  * *** * * ** * *   ***  *******    ***    ***    *  * *** ** ***   **  0;
 * * ***** **  ** *   *** *** ***** * **  *  * ** ***   
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}


int main()
{
*  *     * **** *
** **     **
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*  * *   ***  ** 
 *  * *  *** ****     **

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);
         ^