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

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


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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**  ***** * ********          *   *** **** *
    {
* ** **  ** *  **   **  *  * **    ** * **** * * * ** ****  * *
 **  **  *****   *  **  *   ** ** *  *  *** *  **  *
  * **  ****** ******   * ****** ******         * *  * * ****  ** ** ** **  ***** **  ** * *   * *  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;

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

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


* * *   *    * *****  ** ****** *** ** 
   ******  *    * * *    
 * ***  ** ** *    * *** *     ***** *   ****  **   1;
 *   **  ***   **** *** 
  * *    *     ****  ** *** 

   return 0;
}


int main()
{
 * ** *      * ** **** ****   * *** a[100];
 ***    ***  ***     *  ** *  b[100];


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

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

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

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