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])
   *  **  ** * * *  ***   ** *  * * **** *** * *** *   *     
 **   * * *** * *********    * ** *    * **  **  * **  ****** *** * ** * *  * 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);
         ^