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


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