func_code_string: #include <bits/stdc++.h>   int any_table[11][11];   struct DammedPascalNUmber {     int tb[13][13];     DammedPascalNUmber() {       int i, j;       for (i = 0; i <= 12; i++)         for (j = 0; j <= i; j++) {           int &r = tb[i][j];           if (j == 0 || i == 0)             r = 1;           else             r = tb[i - 1][j - 1] + tb[i - 1][j];         }     }     int count(int n, int m) { return tb[n][m]; }   } pas;   int any(int dig, int amo) {     if (dig < amo) return 0;     if (amo < 0) return 0;     if (dig == 0) return 1;     int &r = any_table[dig][amo];     int i;     if (r >= 0) return r;     r = 1;     for (i = 0; i < amo; i++) r *= 2;     for (; i < dig; i++) r *= 8;     r *= pas.count(dig, amo);     return r;   }   int check(int m, int n) {     int i, j, t, r = 0;     for (i = 1; i <= m; i++) {       char str[15];       t = 0;       sprintf(str,  %d , i);       for (j = 0; str[j]; j++)         if (str[j] ==  4  || str[j] ==  7 ) t++;       if (t == n) r++;     }     return r;   }   int a[13];   int dfs(int party, int quta) {     int r = 0, i;     if (party == 6) {       return 1;     }     for (i = quta; i >= 0; i--)       if (a[i] > 0) {         int t = a[i];         a[i]--;         r = (1LL * r + 1LL * t * 1LL * dfs(party + 1, quta - i) +              1LL * 1000000007) %             1000000007;         a[i]++;       }     return r;   }   void test(int n, int m) { printf( any(%d,%d)=%d n , n, m, any(n, m)); }   void test2(int m, int n) {     printf( (%d,%d)=%d a[%d]=%d n , m, n, check(m, n), n, a[n]);   }   int main() {     memset(any_table, -1, sizeof(any_table));     int m, s, i, j, k, sn, lucked;     while (~scanf( %d , &m)) {       memset(a, 0, sizeof(a));       char str[15];       sprintf(str,  %d , m);       for (sn = 0; str[sn]; sn++)         ;       for (j = sn; j > 0; j--) {         a[j] = 0;         lucked = 0;         for (i = 0; i < sn; i++) {           int p = 0, q = 0;           k = str[i] -  0  - 1;           for (; k >= 0; k--)             if (k == 4 || k == 7)               q++;             else               p++;           if (p) a[j] += p * any(sn - i - 1, j - lucked);           if (q) a[j] += q * any(sn - i - 1, j - lucked - 1);           if (str[i] ==  4  || str[i] ==  7 ) {             lucked++;           }           if (i == sn - 1 && lucked == j) a[j]++;         }       }       a[0] = m;       for (i = 1; i <= sn; i++) a[0] -= a[i];       int ans = 0;       for (i = 1; i <= sn; i++)         if (a[i]) {           ans = (1LL * ans + 1LL * a[i] * dfs(0, i - 1) + 1LL * 1000000007) %                 1000000007;         }       printf( %d n , ans);     }   }   