instructions
Due Date: Wednesday 4th April 2018 at 11:55PM In this assignment, we will work on c-strings. In order to store c-strings, we will use C++ static or dynamic character arrays. You are not allowed to use the C++ string data type in this assignment. Read the restriction section below. Consider the main program together with function headers given below: #include using namespace std; int stringLength(const char* s) { //returns the number of printable characters in s } int countChars(const char* s, const char ch) { //returns the number of times the character ch is found in s } int findChar(const char* s, const char ch, const int startIndex, const int lastIndex) { /* returns the first index where the character ch is found in s starting from startIndex (inclusive) upto lastIndex (exclusive) If ch is not found in s in the interval, it returns -1 This function must first validate both the startIndex and lastIndex. That is, if lastIndex > stringLength(s) or startIndex < 0 it must return -1 */ } void rotateString(char* s, const int r) { /* Rotate the characters of s by r units If r > 0, rotate the characters of s to the left If r < 0, rotate the characters of s to the right Please note the value of r can be any integer even larger than the length of s */ } void append(char*& s, const char ch) { /* Appends the character ch to the c-string s. That is ch is added to the end of s The parameter s is assumed to be a dynamic array (NOT a static one) */ } (Ph.D.) Page 1 void append(char*& s1, const char* s2) { /* Appends all the characters of s2 to s1 The parameter s1 is assumed to be a dynamic array (NOT a static one) */ } void removeAll(char*& s, const char ch) { /* remove all the occurences of the character ch from the c-string s The parameter s is assumed to be a dynamic array (NOT a static one) */ } char* zigzagMerge(const char *s1, const char* s2) { /* create and return a new c-string by merging (putting in one) s1 and s2 in zigzag form. That is first character of the new c-string is the first character of s1 second character of the new c-string is the first character of s2 third character of the new c-string is the second character of s1 fourth character of the new c-string is the second character of s2 fifth character of the new c-string is the third character of s1 sixth character of the new c-string is the third character of s2 etc When either s1 or s2 reaches to its end, the remaining characters of the other are appended to new c-string Example, zigzagMerge of “abc” and “defgh” will be “adbecfgh” */ } bool isAnagram(const char *s1, const char* s2) { /* returns true if s1 and s2 contain same distinct characters apearing same number of times in both s1 and s2 otherwise returns false That is, this function returns true if s1 and s2 are permutations (re-arrangements) of same characters */ } bool isSubstring(const char *s1, const char* s2) { /* returns true is s1 is a substring of s2 otherwise returns false Definition: s1 is a substring of s2 if s1 is found in s2. That is all characters of s1 are found TOGETHER in s2 in the SAME ORDER as they appear in s1 Example “set” is a substring of “massachussettes” But “ets” is not substring of “massachussettes” */ } int countWords(const char* s) { /* Given a c-string that contains some words separated by spaces, return the number of words in the c-string. (Ph.D.) Page 2 In this case, a word means some characters with no space in between. Example: If the c-string parameter is “What a nice Then you see that there are FOUR words in this c-string, namely 1. What 2. a 3. nice 4. problem Your function then must return 4 problem”. For simplicity, 1. Assume that there are no spaces at the beginning or at the end of the c-string 2. But a word may be separated from another word by more than one space 2. Assume the parameter does not contain any punctuation marks such as full stop or comma. */ } int main() { /* This main program is designed to test the functions you need to implement. You should NOT remove any line of code from this main program. But you may add more test code in the main program if you like. */ //Test stringLength function cout << endl; char s1[] = “massachussettes”; cout << s1 << ” has ” << stringLength(s1) << ” characters” << endl; //Test countChars function cout << endl; char ch = ‘s’; int c = countChars(s1, ch); cout << ch << ” appears ” << c << ” times in ” << s1 << endl; //Test findChar function cout << endl; int index = findChar(s1, ch, 10, 14); if (index == -1) cout << ch << ” is not found in ” << s1 << ” between indexes [10, 14)” << endl; else cout << ch << ” is found at index ” << index << ” in ” << s1 << ” between indexes [10, 14)” << endl; //Test rotateString function cout << endl; char temp1[] = “massachussettes”; rotateString(temp1, 2); cout << s1 << ” rotated 2 units to the left becomes ” << temp1 << endl; char temp2[] = “massachussettes”; rotateString(temp2, -19); cout << s1 << ” rotated 19 units to the right becomes ” << temp2 << endl; //Test append function (appending a character to c-string) cout << endl; char* s2 = new char[1]; s2[0] = ‘ ’; cout << “Given the c-string ” << s2 << endl; ch = ‘a’; append(s2, ch); cout << “tAppending ” << ch << ” results to ” << s2 << endl; ch = ‘b’; append(s2, ch); (Ph.D.) Page 3 cout << “tAppending ” << ch << ” results to ” << s2 << endl; //Test append function (appending a c-string to a c-string) cout << endl; cout << “Appending ” << s1 << ” to ” << s2 << “, we get “; append(s2, s1); cout << s2 << endl; //Test removeAll function cout << endl; ch = ‘e’; cout << “Removing all occurences of ” << ch << ” from ” << s2 << “, we get “; removeAll(s2, ch); cout << s2 << endl; ch = ‘t’; cout << “Removing all occurences of ” << ch << ” from ” << s2 << “, we get “; removeAll(s2, ch); cout << s2 << endl; ch = ‘s’; cout << “Removing all occurences of ” << ch << ” from ” << s2 << “, we get “; removeAll(s2, ch); cout << s2 << endl; //Test zigzagMerge function cout << endl; char *s3 = zigzagMerge(s1, s2); cout << “The zigzag merge of ” << s1 << ” and ” << s2 << ” is ” << s3 << endl; //Test isAnagram function cout << endl; char s4[] = “htsemsaesuatscs”; bool flag = isAnagram(s1, s4); if (flag) cout << s1 << ” and ” << s4 << ” are anagrams” << endl; else cout << s1 << ” and ” << s4 << ” are not anagrams” << endl; //Test isSubstring function cout << endl; flag = isSubstring(s1, s4); if (flag) cout << s1 << ” is a substring of ” << s4 << endl; else cout << s1 << ” is not a substring of ” << s4 << endl; char s5[] = “abort”; char s6[] = “abcabodefaborhuhabortabunny”; flag = isSubstring(s5, s6); if (flag) cout << s5 << ” is a substring of ” << s6 << endl; else cout << s5 << ” is not a substring of ” << s6 << endl; //Test countWords function cout << endl; char s7[] = “”; c = countWords(s7); cout << “There are ” << c << ” words in ” << s7 << endl; char s8[] = “Test”; c = countWords(s8); cout << “There are ” << c << ” words in ” << s8 << endl; (Ph.D.) Page 4 char s9[] = “Nice one”; c = countWords(s9); cout << “There are ” << c << ” words in ” << s9 << endl; char s10[] = “This is a nice assignment and hopefully an interesting as well”; c = countWords(s10); cout << “There are ” << c << ” words in ” << s10 << endl; //Delete dynamically allocated memories delete[] s2; delete[] s3; system(“Pause”); return 0; } Your Task You are required to copy the given main program together with the function headers exactly as they are with no change whatsoever and then implement the missing functions so that the program works correctly. Each function is described in detail in the comments given together with the function headers. Some sample runs are given below for your reference. Of course you can write additional helper functions that you can call from within your functions; but you are not allowed to make any change to the given main program and the function headers. Once you are done with your assignment, you can add more code to the main program if you would like to test your functions further. Of course I will only mark your functions; the main program is provided mainly to help you test your functions. Restrictions You are required to use C++ static or dynamic character arrays to store c-strings. You are NOT allowed to use C++ string data type in this assignment. You are not allowed to use any C++ string data type variable for any purpose. If you use a C++ string data type variable for any purpose in your program, you will automatically get zero mark. Moreover, you are allowed to add any include directive. Specifically you are not allowed to include string, cstdlib or math libraries. Also you are not allowed to use any built-in functions of c-strings. Submission Format You are required to submit your program online through Moodle. You will find a submission button for Assignment 1 on Moodle on Week 12 and you are required to upload the source code of your C++ program. No assignment is submitted through email or hard copy; you must upload your work onto Moodle before the due date. Submission Due Date The due date to upload your program online through Moodle is Wednesday 2 th April 2018 at 11:55PM. Moodle will not allow you to upload after this date and time. Marking A non working program will automatically get zero. A program that works but doesn’t give right output or gives partial right output will lose marks depending how severe its shortcoming is. This assignment carries 10% of the total course marks. (Ph.D.) Page 5 Sample Run of the program massachussettes has 15 characters s appears 5 times in massachussettes s is not found in massachussettes between indexes [10, 14) massachussettes rotated 2 units to the left becomes ssachussettesma massachussettes rotated 19 units to the right becomes ttesmassachusse Given the c-string Appending a results to a Appending b results to ab Appending massachussettes to ab, we get abmassachussettes Removing all occurences of e from abmassachussettes, we get abmassachusstts Removing all occurences of t from abmassachusstts, we get abmassachusss Removing all occurences of s from abmassachusss, we get abmaachu The zigzag merge of massachussettes and abmaachu is maabsmsaaacchhuussettes massachussettes and htsemsaesuatscs are anagrams massachussettes is not a substring of htsemsaesuatscs abort is a substring of abcabodefaborhuhabortabunny There are 0 words in There are 1 words in Test There are 2 words in Nice one There are 11 words in This is a nice assignment and hopefully an interesting as well (Ph.D.) Page 6