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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* **  * **   *  *  *  *** * *  *  * ***      *****  *  * **** **   ***   *  *
** ***  * * *   **   * * *  ***  ***   ** ****   *    **  ********** ** ***   *    ** ** **   ** * ** *  *  ** *  1;
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* **  **   **  * ** **   **     *     ***  *  *  * ** *   *
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 * ** * *** ** *      * *    **   * *      ** ******** *  
*   **       ** * ***   *
}


int main()
{
*   *   * **  *
*    * ** ****   **  
*  * ** *  * ** ",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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    {
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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];


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

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

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

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