print a string with printf in c 2b 2b

1#include <cstdio>
2
3int main()
4{
5    char ch = 'a';
6    float a = 5.0, b = 3.0;
7    int x = 10;
8
9    printf("%.3f / %.3f = %.3f \n", a,b,a/b);
10    printf("Setting width %*c \n",5,ch);
11    printf("Octal equivalent of %d is %o \n",x,x);
12
13    return 0;
14}

1//can't print with printf, since string is a C++ class obj and print %s 
2//doesn't recognize
3//can do
4printf("%s", str.c_str()) //converts string to c str (char array)
5  
6  //or just use cout<<str; 
7  
8  //string assignment 
9  str1=str2; //or
10str1.assign(str2) 

1#include <cstdio>
2int printf( const char *format, ... );
3cout<<printf;
4