Using signed and unsigned modifiers

/* 0901.c: Using signed and unsigned modifiers */
#include <stdio.h>

main()
{
    signed char ch;
    int x;
    unsigned int y;

    ch = 0xFF;
    x = 0xFFFF;
    y = 0xFFFFu;
    printf("The decimal of signed 0xFF is %d.\n", ch);
    printf("The decimal of signed 0xFFFF is %d.\n", x);
    printf("The decimal of unsigned 0xFFFFu is %u.\n", y);
    printf("The hex of decimal 12345 is 0x%X.\n", 12345);
    printf("The hex of decimal -12345 is 0x%X.\n", -12345);
    return 0;
}