I just started learning C and copied this directly from a book. Can someone tell me why this doesn't work?

```
#include <stdio.h>

int main (void)
{
    int     integerVar = 100;
    float   floatingVar = 331.79;
    double  doubleVar = 8.44e+11;
    char    charVar = "W";

    _Bool   boolVar = 0;

    printf ("integerVar = %i\n", integerVar);
    printf ("floatingVar = %f\n", floatingVar);
    printf ("doubleVar = %e\n", doubleVar);
    printf ("doubleVar = %g\n", doubleVar);
    printf ("charVar = %c\n", charVar);

    printf ("boolVar = %i\n", boolVar);

    return 0;
}

```

I get this error:

```
datatypes.c: In function ‘main’:
datatypes.c:8: warning: initialization makes integer from pointer without a cast

```