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


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);
         ^