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 ****   **   *  ** ** * * ****
    *  *  * *****  * *** *    * *   ** *   **    ** ** ** ** **** {
  **  *  *    *   ** *** *      *    * * *** * **   ***   ** **    ***    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)
{
  **   ** *        **    *** * * **   i<pl; 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;
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 *** *   *****         *  *   *****   *
*  *  *  * *  ** * *      *     ***  *** 
 * ****  * **** * ** * *  ****   * ***
    {
*  ****** *** ** *  ** * *  *   **** * ****  * **  **** ***     ** 
*   * ** * * * ****** ** * * ***   **      *  *   **    * 
 * **** **** * *    **  *  ***  * *   *** *  ** * *****  ** * ****** * * *  *   **** * ***  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;

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

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


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