#include <string>
#include <vector>
#include <iostream>
using namespace std;
string lookup[200];
using llu = unsigned long long;
vector<int> results;
llu k, a, b;
int a_digits, b_digits;
llu sum_squares(llu i)
{
llu val = i;
llu sum = 0;
while (val)
{
int t = val % 10;
val /= 10;
sum += t*t;
}
return sum;
}
void solveA(llu a, llu b, llu k)
{
llu start = a;
if (start <= k)
start = k;
else
start += k - a % k;
while (start <= b)
{
if (k * sum_squares(start) == start)
results.push_back(1);
start += k;
}
}
int dig_count(llu num)
{
int n = 0;
while (num) {
num /= 10;
n++;
}
return n;
}
llu max_val(llu value, int digs, int max_digs)
{
while (digs < max_digs)
{
value *= 10;
value += 9;
++digs;
}
return value;
}
void solveB(llu value, llu square_sum, int digits)
{
if (value > b)
return;
//sprawdz
if (value >= a)
{
if (square_sum * k == value)
{
results.push_back(value);
}
}
int new_digits = digits + 1;
for (int i = 0; i <= 9; ++i)
{
llu new_value = value * 10 + i;
if (new_value < b)
{
llu new_sq_sum = square_sum + i*i;
llu m_value = max_val(new_value, new_digits, b_digits);
llu full_sq_sum = new_sq_sum * k;
if (full_sq_sum <= m_value)
{
if (sum_squares(m_value) * k >= new_value)
solveB(new_value, new_sq_sum, new_digits);
}
}
}
}
int main(void)
{
//while (true)
{
cin >> k >> a >> b;
//k = 51; a = 1; b = 1000000000000000000;
if ((b - a) / k < 10000000)
solveA(a, b, k);
else
{
a_digits = dig_count(a);
b_digits = dig_count(b);
int digits = 1;
for (int i = 1; i <= 9; ++i)
{
llu value = i;
llu square_sum = value * value;
solveB(value, square_sum, digits);
}
}
cout << results.size() << endl;
results.clear();
}
return 0;
}
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 | #include <string> #include <vector> #include <iostream> using namespace std; string lookup[200]; using llu = unsigned long long; vector<int> results; llu k, a, b; int a_digits, b_digits; llu sum_squares(llu i) { llu val = i; llu sum = 0; while (val) { int t = val % 10; val /= 10; sum += t*t; } return sum; } void solveA(llu a, llu b, llu k) { llu start = a; if (start <= k) start = k; else start += k - a % k; while (start <= b) { if (k * sum_squares(start) == start) results.push_back(1); start += k; } } int dig_count(llu num) { int n = 0; while (num) { num /= 10; n++; } return n; } llu max_val(llu value, int digs, int max_digs) { while (digs < max_digs) { value *= 10; value += 9; ++digs; } return value; } void solveB(llu value, llu square_sum, int digits) { if (value > b) return; //sprawdz if (value >= a) { if (square_sum * k == value) { results.push_back(value); } } int new_digits = digits + 1; for (int i = 0; i <= 9; ++i) { llu new_value = value * 10 + i; if (new_value < b) { llu new_sq_sum = square_sum + i*i; llu m_value = max_val(new_value, new_digits, b_digits); llu full_sq_sum = new_sq_sum * k; if (full_sq_sum <= m_value) { if (sum_squares(m_value) * k >= new_value) solveB(new_value, new_sq_sum, new_digits); } } } } int main(void) { //while (true) { cin >> k >> a >> b; //k = 51; a = 1; b = 1000000000000000000; if ((b - a) / k < 10000000) solveA(a, b, k); else { a_digits = dig_count(a); b_digits = dig_count(b); int digits = 1; for (int i = 1; i <= 9; ++i) { llu value = i; llu square_sum = value * value; solveB(value, square_sum, digits); } } cout << results.size() << endl; results.clear(); } return 0; } |
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