#ifdef __cplusplus

#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <string>
#include <iostream>
#include <algorithm>
#include <vector>
#include <set>
#include <map>
#include <cmath>

// forprak

#include <unistd.h>
#include <fcntl.h>
#include <climits>
#include <elf.h>
#include <sys/stat.h>
#include <dirent.h>

// endforprak

using namespace std;

#else

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <unistd.h>
#include <fcntl.h>
#include <limits.h>
#include <elf.h>
#include <stdbool.h>
#include <time.h>
#include <sys/stat.h>
#include <dirent.h>

#endif

typedef long long ll;
typedef struct tm tm;

#define sqrt(x) (sqrt(abs((x))))
#define mp make_pair
#define pb push_back
#define sqr(o) ((o)*(o))

int main(int argc, char ** argv)
{
    //freopen("input.txt", "r", stdin); //freopen("output.txt", "w", stdout);
    //freopen("highways.in", "r", stdin);freopen("highways.out", "w", stdout);

    DIR * d;
    if (!(d = opendir(argv[1])))
    {
        return 0;
    }

    char path[PATH_MAX] = {0};
    strcpy(path, argv[1]);
    int l = strlen(path);
    path[l++] = '/';
    char * ppath = path + l;


    ll ans = 0;
    struct dirent *file;
    while ((file = readdir(d)))
    {
        struct stat s;
        strcpy(ppath, file->d_name);
        stat(path, &s);
        if (S_ISREG(s.st_mode) && !(S_ISLNK(s.st_mode)))
        {
            //printf("%s --> %d\n", path, s.st_size);
            ans += s.st_size;
        }
    }

    printf("%lld\n", ans);

    closedir(d);

    return 0;
}