#include <cstdio>
#include <cstring>
#include <cmath>
#include <cassert>
#include <iostream>
#include <algorithm>
#include <iterator>
#include <string>
#include <vector>
#include <queue>
#include <bitset>
#include <utility>
#include <stack>
using namespace std;
typedef long long LL;
typedef pair<int,int> PII;
typedef vector<int> VI;
#define MP make_pair
#define FOR(v,p,k) for(auto v=(p);v<=(k);++v)
#define FORD(v,p,k) for(auto v=(p);v>=(k);--v)
#define REP(i,n) for(auto i=0;i<(n);++i)
#define VAR(v,i) __typeof(i) v=(i)
#define FOREACH(i,c) for(VAR(i,(c).begin());i!=(c).end();++i)
#define PB push_back
#define ST first
#define ND second
#define SIZE(x) (int)x.size()
#define ALL(c) c.begin(),c.end()
#define ODD(x) ((x)%2)
#define EVEN(x) (!(ODD(x)))
template <typename T>
inline int sgn(T val) {
return (T{} < val) - (val < T{});
}
template <typename T>
inline T ceil(T x, T y) {
return x/y + sgn(x%y);
}
inline auto f_n(LL n) {
LL res{};
while (n) {
auto d = n % 10;
res += d*d;
n /= 10;
}
return res;
}
int main() {
ios_base::sync_with_stdio(0);
LL k, a, b;
cin >> k >> a >> b;
LL from = max(1LL, ceil(a, k));
LL to = min(9*9*17LL, b/k);
LL res{};
FOR(possible_f_n,from,to) {
auto n = k * possible_f_n;
res += (possible_f_n == f_n(n));
}
cout << res << endl;
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 | #include <cstdio> #include <cstring> #include <cmath> #include <cassert> #include <iostream> #include <algorithm> #include <iterator> #include <string> #include <vector> #include <queue> #include <bitset> #include <utility> #include <stack> using namespace std; typedef long long LL; typedef pair<int,int> PII; typedef vector<int> VI; #define MP make_pair #define FOR(v,p,k) for(auto v=(p);v<=(k);++v) #define FORD(v,p,k) for(auto v=(p);v>=(k);--v) #define REP(i,n) for(auto i=0;i<(n);++i) #define VAR(v,i) __typeof(i) v=(i) #define FOREACH(i,c) for(VAR(i,(c).begin());i!=(c).end();++i) #define PB push_back #define ST first #define ND second #define SIZE(x) (int)x.size() #define ALL(c) c.begin(),c.end() #define ODD(x) ((x)%2) #define EVEN(x) (!(ODD(x))) template <typename T> inline int sgn(T val) { return (T{} < val) - (val < T{}); } template <typename T> inline T ceil(T x, T y) { return x/y + sgn(x%y); } inline auto f_n(LL n) { LL res{}; while (n) { auto d = n % 10; res += d*d; n /= 10; } return res; } int main() { ios_base::sync_with_stdio(0); LL k, a, b; cin >> k >> a >> b; LL from = max(1LL, ceil(a, k)); LL to = min(9*9*17LL, b/k); LL res{}; FOR(possible_f_n,from,to) { auto n = k * possible_f_n; res += (possible_f_n == f_n(n)); } cout << res << endl; return 0; } |
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