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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*   ** * **   * *  * *   ** **   *
* ****  ***** {
**   *  *** **  ** *     ***  *** ***
***   *  *  ** *   * ***   * **   {
*  **     ** * *  ***   * **    ** *  **   **  * * *  *     * *    **     **** 
*   * *** *   * *  ** * **    ****  *   *****      *** *** **   {
 *                     *** * **     c=0;
 * **  *** *** **      * * *  **   *   **      *  **     * }
  **  *   *** * *    ****  **        * else  * * ****      ** * *  *  *
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*****     ****    *  *  * **  * *   *  *  *      **  *****     *** }
       * *** * ** * *****   ** *  }
***    * *** *  
 ** **   ** *  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

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


int main()
{
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* **** ** ****  
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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);
 ** *      *** ***   **   * ** *   *     * **  *  * **** * *    *** **
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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])
{
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* * *    *  *  * *   *****    count=0;
 ***   *  ****** ** * **  *  len;

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

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


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

   return 0;
}


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


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