#include <string>

string a;
a="hello";
a[3]='x';
int w = a.length();
string b = a + "123";



char c[100];
c[3]='x';
c="hello";

#include <string.h>

void strcpy(char dest[], char src[])
{ for (int i=0; true; i+=1)
  { dest[i]=src[i];
    if (src[i] == '\0') 
      break; } }

void strncpy(char dest[], char src[], int size)
{ for (int i=0; i<size; i+=1)
  { dest[i]=src[i];
    if (src[i] == '\0') 
      break; } }

int strlen(char s[])
{ for (int i=0; true; i+=1)
    if (s[i]=='\0')
      return i; }

int strcmp(char a[], char b[])
{ for (int i=0; true; i+=1)
  { if (a[i] < b[i])
    { return -1; }
    else if (a[i] > b[i])
    { return +1; }
    else if (a[i] == '\0')
    { return 0; } } } 

int strcmp(char a[], char b[])   // standard version
{ for (int i=0; true; i+=1)
  { int d = a[i]-b[i];
    if (d!=0)
    { return d; }
    else if (a[i] == '\0')
    { return 0; } } } 

int strcasecmp(char a[], char b[])   // standard version
{ for (int i=0; true; i+=1)
  { int d = toupper(a[i])-toupper(b[i]);
    if (d!=0)
    { return d; }
    else if (a[i] == '\0')
    { return 0; } } } 


char xxx[10];
int important = 4737;
string_assign(xxx, "jasdgjasdfljsflasdjkf");

   if (strcmp("cat", "bat")==0)
   { cout << "they are the same"; }

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  char one[25];
  char * two;

while (1)
{ two = "hello";   // no
  strcpy(two, "hello");   // OK
  one = "hello";   // no
  cout << two;
  two[2]='x'; }

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