Article Categories
- All Categories
-
Data Structure
-
Networking
-
RDBMS
-
Operating System
-
Java
-
MS Excel
-
iOS
-
HTML
-
CSS
-
Android
-
Python
-
C Programming
-
C++
-
C#
-
MongoDB
-
MySQL
-
Javascript
-
PHP
-
Economics & Finance
Articles by sudhir sharma
Page 11 of 98
Write a bash script to print a particular line from a file in C
In C programming, we can read and print a specific line from a file using file handling functions. This involves opening the file, reading through it line by line, and printing the desired line number. Syntax FILE *fopen(const char *filename, const char *mode); char *fgets(char *str, int n, FILE *stream); int fclose(FILE *stream); Method 1: Using Line Counter This approach reads the file line by line and uses a counter to track the current line number − Note: Create a text file named "text.txt" in the same directory with some content before ...
Read MoreWrite a C program to print 'ABCD' repeatedly without using loop, recursion and any control structure
In this problem, we have to write a program in C that will print a string 'ABCD' repeatedly without using loop, recursion and any control structure. So, we will have to call or run the same block of code infinite times but without using loop, recursion or control structure which are the most common methods to perform the task. For this, we will run the same program multiple times instead of looping. This will perform our task within the given constraints. The system() method can be employed inside the code that will call the program infinite times. Syntax ...
Read MoreWriting C/C++ code efficiently in Competitive programming
In competitive programming, writing efficient C code is crucial for achieving better performance and rankings. Fast execution and optimal memory usage can make the difference between acceptance and time limit exceeded. Key Concepts Template − Code that works with different data types without rewriting Macro − Named code fragment that gets replaced during preprocessing Dynamic Arrays − Arrays that can resize during runtime Essential Optimization Techniques Fast Input/Output Methods Using scanf() and printf() instead of slower alternatives provides significant performance improvements ? #include int main() { ...
Read MoreWriting OS Independent Code in C/C++
Writing OS-independent code in C allows programs to run across different operating systems without modification. This is achieved using preprocessor macros that detect the target platform at compile time. Syntax #ifdef MACRO_NAME // OS-specific code #elif defined(ANOTHER_MACRO) // Alternative OS code #else // Default code #endif Common OS Detection Macros GCC and other C compilers define platform-specific macros automatically − _WIN32 − Defined for 32-bit and 64-bit Windows _WIN64 − Defined only for 64-bit Windows __unix__ − Defined for Unix-like ...
Read MorePredefined Identifier __func__ in C
The __func__ is a predefined identifier in C that provides the name of the current function. It was introduced in C99 standard and is automatically available in every function without any declaration. Syntax __func__ The __func__ identifier is implicitly declared as if the following declaration appears at the beginning of each function − static const char __func__[] = "function-name"; Example 1: Basic Usage Here's a simple example showing how __func__ returns the current function name − #include void function1(void) { printf("Current function: ...
Read MorePrint * in place of characters for reading passwords in C
In C programming, when handling passwords, it's important to hide the actual characters from being displayed on screen for security reasons. This involves replacing each character of the password with an asterisk (*) symbol. Let's take an example to understand the problem − Input: password Output: ******** Syntax for(int i = 0; i < strlen(password); i++){ printf("*"); } Example 1: Using Predefined Password String The below program demonstrates how to replace each character of a password string with asterisks ? #include #include ...
Read MorePrint 1 2 3 infinitely using threads in C
In C programming, we can print the sequence "1 2 3" infinitely using multiple threads with proper synchronization. This demonstrates thread coordination using mutexes and condition variables to ensure orderly execution. Syntax pthread_create(&thread_id, NULL, thread_function, argument); pthread_mutex_lock(&mutex); pthread_cond_wait(&condition, &mutex); pthread_cond_signal(&condition); pthread_mutex_unlock(&mutex); Installation: On Linux systems, compile with: gcc filename.c -lpthread Example This program creates three threads that print numbers 1, 2, and 3 in sequence infinitely. Each thread waits for its turn using condition variables − #include #include pthread_cond_t cond1 = PTHREAD_COND_INITIALIZER; pthread_cond_t cond2 = PTHREAD_COND_INITIALIZER; ...
Read MorePrint 2D matrix in different lines and without curly braces in C/C++
Here, we will see how to print a 2D matrix in C programming language without using curly braces. This technique uses a clever approach to eliminate the need for braces in nested loops. Curly braces are separators in C that define separate code blocks in the program. Without curly braces, defining scopes is difficult, but we can use a shorthand technique to achieve the same result for simple operations. Syntax for (int i = 0; i < rows; i++) for (int j = 0; j < cols; j++) ...
Read MorePrint colored message with different fonts and sizes in C
In C programming, the graphics.h library provides functions to customize text output with different colors, fonts, and sizes. This library is primarily used in graphics programming to create visually appealing text displays on the screen. Note: The graphics.h library requires Turbo C/C++ or compatible compilers. For modern compilers, you may need to install graphics libraries like WinBGIm or use alternative approaches. Key Graphics Functions for Text Formatting 1. setcolor() Function The setcolor() function changes the color of the output text − Syntax void setcolor(int color); Example #include ...
Read MoreC Program for Activity Selection Problem
The activity selection problem is a classic optimization problem where we are given a set of activities with their starting and finishing times. The goal is to select the maximum number of activities that can be performed by a single person, given that only one activity can be performed at a time. This problem is efficiently solved using a greedy algorithm approach. The greedy algorithm makes locally optimal choices at each step, hoping to find a global optimum. It selects activities based on their finishing times in ascending order. Syntax void activitySelection(int start[], int finish[], int ...
Read More