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void *malloc(unsigned long);
int printf(char *, ...);
long atol(char *);
void exit(int);
int open(char *, int, int);
long read(int, void *, unsigned long);
void insertion_sort(int *a, long n)
{
long i, j;
for (i = 1; i < n; ++i) {
for (j = i; j > 0; --j) {
if (a[j] < a[j-1]) {
int tmp = a[j];
a[j] = a[j-1];
a[j-1] = tmp;
} else {
break;
}
}
}
}
void *read_arr(int fd, int *len)
{
int size = 1024 * 1024 * 20;
int i;
char *arr = malloc(size);
for (i = 0; ; ) {
int rd = read(fd, arr + i, size - i);
if (rd == -1)
exit(2);
if (rd == 0)
break;
i += rd;
}
printf("input is collected\n");
*len = i;
return arr;
}
int main(int argc, char **argv)
{
int i, len;
unsigned int sum = 0;
int *arr;
int fd;
if (argc != 2) {
printf("%d\n", argc);
return 1;
}
len = atol(argv[1]);
fd = open(argv[1], 0, 0);
if (fd == -1)
return 1;
arr = read_arr(fd, &len);
len /= 4;
if (len != 64000)
return 10;
insertion_sort(arr, len);
for (i = 0; i < len; ++i)
sum = 2 * sum + arr[i];
printf("%u\n", sum);
return 0;
}
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