#define _POSIX_C_SOURCE 200809L
#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>

void leftshift(unsigned char *str,int nshiftleft, uint64_t *value)
{
    uint64_t x = str[0];
    x = x << nshiftleft;
    *value = x;
}

int main()
{
    unsigned char s[] = { 'A', 0 };
    uint64_t result;

    leftshift(s, 56, &result);
    printf("%" PRIx64 "\n", result);
}