1	CS 211: Introduction to Computer Programming II Instructor: Brian M. Dennis Teaching Assistants: Tom Lechner, Bin Lin http://www.cs.northwestern.edu/~bmd/cs211/
2	Linear Search #include <iostream> using namespace std; int linearSearch(const int a[], int k, const int size); int main() { const int arraySize = 100; int a[arraySize]; int key; for (int i = 0; i < arraySize; i++) { a[i] = 2 * i; } cout << "Enter integer search key: "; cin >> key; int element = linearSearch(a, key, arraySize); if (element != -1) { cout << "Found value in element: " << element << endl; } else { cout << "Value not found" << endl; } return 0; }
3	Linear Search int linearSearch(const int array[], int key, int sizeOfArray) { for (int j = 0; j < sizeOfArray; j++) { if (array[j] == key) { return j; } } return -1; } int linearSearch(const int array[], int key, int sizeOfArray) { const int t_array = array; while (t_array < (array + sizeOfArray)) { if (t_array++ == key) { return (t_array – array – 1); } } return -1; }
4	Binary Search #include <iostream> using namespace std; int binarySearch(const int a[], int k, int low, int high, int size) int main() { const int arraySize = 100; int a[arraySize]; int key; for (int i = 0; i < arraySize; i++) { a[i] = 2 * i; } cout << "Enter integer search key: "; cin >> key; int element = binarySearch(a, key, 0, arraySize – 1, arraySize); if (element != -1) { cout << "Found value in element: " << element << endl; } else { cout << "Value not found" << endl; } return 0; }
5	Binary Search int binarySearch(const int a[], int searchKey, int low, int high, int size) { int middle; while (low <= high) { middle = (low + high) / 2; if (searchKey == a[middle]) { return middle; } else if (searchKey < a[middle]) { high = middle – 1; } else { low = middle + 1; } } return -1; }
6	const declaration // nonconstant ptr to nonconstant data #include <cctype> void convertToUppercase(char sPtr) { while (sPtr != '\0') { if (islower( sPtr )) { sPtr = toupper( *sPtr ); } ++sPtr; } }
7	const declaration // nonconstant ptr to constant data void printCharacters((const char)* sPtr) { for ( ; sPtr != '\0'; sPtr++) { cout << sPtr; *sPtr = 'A'; // Should be an error } }
8	const declaration // constant ptr to nonconstant data int main() { int x, y; int * const ptr = &x; *ptr = 7; ptr = &x; return 0; }
9	const declaration // constant ptr to constant data int main() { int x = 5, y; const int const ptr = &x; ptr = 7; ptr = &y; return 0; }
10	String Functions // #include <cstring> char strcpy(char s1, const char s2); char strncpy(char* s1, const char* s2, size_t n); char* strcat(char* s1, const char s2); char strncat(char s1, const char s2, size_t n); int strcmp(const char* s1, const char s2); int strncmp(const char s1, const char* s2, size_t n); size_t strlen(const char *s);
11	String length #include <cstring> #include <iostream> using namespace std; int main(int argc, char* argv[]) { int total_length = 0; for(int i = 1; i < argc; i++) { total_length += strlen(argv[i]); } cout << "Total characters: " << total_length << endl; return 0; }
12	String copying #include <iostream> #include <cstring> using namespace std; int main(int argc, char *argv[]) { const int BUF_SIZE = 1024; char buf[BUF_SIZE] = { '\0' }; for(int i = 1; i < argc; i++) { strcpy(buf, argv[i]); } return 0; }
13	String concatenation #include <iostream> #include <cstring> using namespace std; int main(int argc, char *argv[]) { const int BUF_SIZE = 1024; char buf[BUF_SIZE] = { '\0' }; for(int i = 1; i < argc; i++) { strcat(buf, argv[i]); } cout << "Command line glommed together.\n"; cout << buf << endl; return 0; }
14	Binary Search w/Strings #include <iostream> using namespace std; int binarySearch(char** a, char* k, int low, int high, int size); int main() { char* strings[] = { "Go", "Northwestern", "Wildkats", "You" }; char search_key[1024]; cout << "Enter string search key: "; cin >> search_key; int element = binarySearch(strings, search_key, 0, 3, 3); if (element != -1) { cout << "Found value in element: " << element << endl; } else { cout << "Value not found" << endl; } return 0;}
15	Binary Search w/Strings int binarySearch(char** a, char* searchKey, int low, int high, int size) { int middle; while (low <= high) { middle = (low + high) / 2; int cmp_res = strcmp(searchKey, a[middle]); if (!cmp_res) { return middle; } else if (cmp_res < 0) { high = middle - 1; } else { low = middle + 1; } } return -1; }
16	Dangling Pointers #include <cstdlib> #include <time> char* random_string(int n_chars) { srand( time(0)); const int max_size = 80; char buf[max_size] = {'\0'}; for (int i = 0; (i < n_chars) && (i < max_size)); i++) { int offset = rand() % 26; buf[i] = 'a' + offset; } return buf; }
17	Dynamic Allocation #include <iostream> #include <cstring> using namespace std; int main(int argc, char* argv[]) { int buf_length = 0; for(int i = 1; i < argc; i++) { buf_length += strlen(argv[i]); } buf_length++; char* buf = new char[buf_length]; buf[0] = '\0'; for (int j = 1; j < argc; j++) { strcat(buf, argv[i]) } cout << "Command line glommed together\n"; cout << buf << endl; delete buf; return 0; }
18	That’s a Wrap Reading Catch up on previously assigned stuff