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

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  ****  ****     *  * 
 * **  * *****        *
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

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   *  * *   **   * ***  *

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


int main()
{
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*** **  *****  *   ",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;
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* *** *  * * *    *  *** * * *****
*    ****  * **   *   **   **  **
    {
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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);
         ^