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


int main()
{
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sl=strlen(s);
pl=strlen(p);


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{

  ****  **** **  *** * * **      *  *    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);
* *  ** ****  *  **  *   *  *  ***** *** ** * *** **  *** **  **** ** *  *    
*  ****   * **   *****    *  *   *  **  *** *  * *
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*** * *  ** * *   ** * ***** * ** * * *       *****  ** * * ** * **      *     ** ***       ** * 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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*  ** *   ***  ***  ***  * **  ******      ** * *  *
** *** ** ** *  *** *  ***


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

   return 0;
}


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


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

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

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 {
**       *  * *      * *  **             **   *   ***    *    **** is a prefix of %s",a,b);
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** ** **** **  ***   **  * *  
  ***    * ****    ***
*  ******** ** ***** * * * * ** ** **     *** *** **** * * *   ** *     * **  * * 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);
         ^