#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main()
{
    char *s = "  \t  0xffffffff  \n  ";

    unsigned int u;
    sscanf(s, "%x", &u);

    char buf[100];
    
    sprintf(buf, "%u\n", u);
    printf("%s", buf);

    snprintf(buf, 5, "%u\n", u);
    printf("%s", buf);
}