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

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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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**  *    ******    **     * **      ** * * **    *  * *
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}


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