abc114_c_755.cpp

// 755 | https://atcoder.jp/contests/abc114/tasks/abc114_c
// Time: O(3^digits(N)); extra space: O(digits(N)).
#include <algorithm>
#include <iostream>
#include <string>
#include <vector>

void solve() {
    long long n;
    std::cin>>n;
    int answer=0;
    auto dfs=[&](auto&& self,long long value,int mask)->void {
        if(value>n)return;
        if(mask==7)++answer;
        for(int i=0;i<3;++i) {
            int digit=3+2*i;
            if(value<=(n-digit)/10&&value*10+digit<=n)self(self,value*10+digit,mask|(1<<i));
        }
    }
    ;
    dfs(dfs,0,0);
    std::cout<<answer<<'\n';
}
int main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    solve();
}