C++ Articles - Page 599 of 719

Text modeBinary modeIn text mode various character translations are performed i.e;“\r+\f” is converted into “”In binary mode, such translations are not performed.To write in the files:ofstream ofs (“file.txt”);Orofstream ofs;ofs.open(“file.txt”);to write in the files: ofstream ofs(“file.txt”, ios::binary);orofstream ofs;ofs.open(“file.txt”, ios::binary);To add text at the end of the file:Ofstream ofs(“file.txt”, ios::app);orofstream ofs;ofs.open(“file.txt”, ios::app);To add text at the end of the file:Ofstreamofs(“file.txt”, ios::app|ios::binary);or ofstream ofs;ofs.open(“file.txt”, ios::app|ios::binary);To read files:ifstream in (“file.txt”);orifstreamin ; in.open(“file.txt”);To read files: ifstream in (“file.txt”, ios::binary);orifstream in ;in.open(“file.txt”, ios::binary);Read More

The C++ function std::algorithm::lexicographical_compare() tests whether one range is lexicographically less than another or not. A lexicographical comparison is the kind of comparison generally used to sort words alphabetically in dictionaries.Declarationtemplate bool lexicographical_compare(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2);AlgorithmBegin    result = lexicographical_compare(v1.begin(), v1.end(), v2.begin(), v2.end())    if (result == true)       Print v1 is less than v2    result = lexicographical_compare(v1.begin(), v1.end(), v2.begin(), v2.end())    if (result == false)       Print v1 is not less than v2 EndExample Live Demo#include #include #include #include using namespace std; int main(void) {    //initialization ... Read More

Let us consider the following example, which uses an array of 3 integers −In CExample Live Demo#include const int MAX = 3; int main () {    int var[] = {10, 100, 200};    int i;    for (i = 0; i < MAX; i++) {       printf("Value of var[%d] = %d", i, var[i] );    }    return 0; }OutputValue of var[0] = 10 Value of var[1] = 100 Value of var[2] = 200In C++Example Live Demo#include using namespace std; const int MAX = 3; int main () {    int var[] = {10, 100, 200};    int i;    for (i = 0; i < MAX; i++) {       cout

This is a C++ program in which we generate a undirected random graph for the given edges ‘e’. This algorithm basically implements on a big network and time complexity of this algorithm is O(log(n)).AlgorithmBegin    Function GenerateRandomGraphs(), has ‘e’ as the number edges in the argument list.    Initialize i = 0    while(i < e)       edge[i][0] = rand()%N+1       edge[i][1] = rand()%N+1       Increment I;    For i = 0 to N-1       Initialize count = 0       For j = 0 to e-1         ... Read More

Searching based on locality of reference, depends upon the memory access pattern data elements are reallocated.Here linear searching method is used to search an element.AlgorithmBegin    int find(int *intarray, int n, int item)    intialize comparisons = 0    for i = 0 to n-1       Increase comparisons    if(item == intarray[i])       Print element with its index    break    if(i == n-1)       Print element not found    return -1    Print Total comparisons    For j = i till i>0       intarray[j] = intarray[j-1]       intarray[0] = ... Read More

Here we will see the Bind function and the placeholders in C++. Sometimes we need to manipulate the operation of some functions as we need. We can use some default parameters to get some essence of manipulating.In C++11, one new feature is introduced, called the bind function. This helps us to do such manipulating in some easier fashion. To use these features, we have to use header file.Bind functions with the help of placeholders helps to determine the positions, and number of arguments to modify the function according to desired outputs.Placeholders are namespaces which detect the position of a ... Read More

Here we will see the Shuffle and random_shuffle in C++. Let us see the random_shuffle first. It is used to randomly rearrange the elements in range [left, right). This function randomly swaps the positions of each element with the position of some randomly chosen positions.We can provide some random generator function to tell which element will be taken in every case. If we do not provide some, it will use its own random generator function.Example Live Demo#include using namespace std; int myRandomGenerator(int j) {    return rand() % j; } main() {    srand(unsigned(time(0)));    vector arr;    for (int ... Read More

Here we will see when we need to create own assignment operator in C++. If a class do not have any pointers, then we do not need to create assignment operator and copy constructor. C++ compiler creates copy constructor and assignment operator for each class. If the operators are not sufficient, then we have to create our own assignment operator.Example Live Demo#include using namespace std; class MyClass { //no user defined assignment operator or copy constructor is present    int *ptr;    public:       MyClass (int x = 0) {          ptr = new int(x);       }    void setValue (int x) {       *ptr = x;    }    void print() {       cout

The C library function char *ctime(const time_t *timer) returns a string representing the localtime based on the argument timer.The returned string has the following format − Www Mmm dd hh:mm:ss yyyy, where Www is the weekday, Mmm the month in letters, dd the day of the month, hh:mm:ss the time, and yyyy the year.The syntax is like below −char *ctime(const time_t *timer)This function takes the pointer to a time_t, which is containing the calendar time. It returns a string containing date, time info in human readable format.Example Live Demo#include #include int main () {    time_t curtime;    time(&curtime); ... Read More

In this section we will see the isnormal() function in C++. This function is present in the cmath library. This function is used to check whether a number is normal or not. The numbers that are considered as non-normal are zeros, infinity or NAN.This function takes float, double or long double values as argument. Returns 1 if the number is normal, otherwise returns 0.Example Live Demo#include #include using namespace std; int main() {    cout