memset c++

// CPP program to illustrate memset 
//works with var adresses ,basically characters but limit its use to -1 and 0 in int
#include <cstring> 
#include <iostream> 
  
using namespace std; 
  
int main() 
{ 
    char str[] = "geeksforgeeks"; 
    memset(str, 't', sizeof(str)); 
    cout << str; 
    return 0; 
} 
output:
tttttttttttttt

#include <bits/stdc++.h> 
using namespace std; 
   
int main() 
{ 
    int a[5]; 
   
    // all elements of A are zero 
    memset(a, 0, sizeof(a)); 
    for (int i = 0; i < 5; i++) 
        cout << a[i] << " "; 
    cout << endl; 
   
    // all elements of A are -1 
    memset(a, -1, sizeof(a)); 
    for (int i = 0; i < 5; i++) 
        cout << a[i] << " "; 
    cout << endl; 
   
    // Would not work 
    memset(a, 5, sizeof(a)); // WRONG 
    for (int i = 0; i < 5; i++) 
        cout << a[i] << " "; 
} 

#include <bits/stdc++.h>
using namespace std;
  
int main()
{
    int a[5];
  
    // all elements of A are zero
    memset(a, 0, sizeof(a));
    for (int i = 0; i < 5; i++)
        cout << a[i] << " ";
    cout << endl;
  
    // all elements of A are -1
    memset(a, -1, sizeof(a));
    for (int i = 0; i < 5; i++)
        cout << a[i] << " ";
    cout << endl;
  
    // Would not work
    memset(a, 5, sizeof(a)); // WRONG
    for (int i = 0; i < 5; i++)
        cout << a[i] << " ";
}

/* memset example */
#include <stdio.h>
#include <string.h>

int main ()
{
  char str[] = "almost every programmer should know memset!";
  memset (str,'-',6);
  puts (str);
  return 0;
}

// Output:
// ------ every programmer should know memset!

0 0 0 0 0 
-1 -1 -1 -1 -1 
84215045 84215045 84215045 84215045 84215045

// memset syntax
void * memset ( void * ptr, int value, size_t num );