abc29d_partial.cpp

#include <bits/stdc++.h>
#include <X11/Intrinsic.h>
#include <iostream>
#include <string>
 
using namespace std;
 
#define all(c) ((c).begin()), ((c).end())
#define dump(c) cerr << "> " << #c << " = " << (c) << endl;
#define iter(c) __typeof((c).begin())
#define tr(i, c) for (iter(c) i = (c).begin(); i != (c).end(); i++)
#define REP(i, a, b) for (int i = a; i < (int)(b); i++)
#define rep(i, n) REP(i, 0, n)
#define mp make_pair
#define fst first
#define snd second
#define pb push_back
 
 
 
typedef unsigned int uint;
typedef long long ll;
typedef unsigned long long ull;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<vll> vvll;
typedef vector<vi> vvi;
typedef vector<double> vd;
typedef vector<vd> vvd;
typedef vector<string> vs;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
 
const int INF = 1 << 29;
const double EPS = 1e-10;
 
template<class T>
bool chmax(T &a, const T &b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}
 
template<class T>
bool chmin(T &a, const T &b) {
    if (b < a) {
        a = b;
        return true;
    }
    return false;
}
 
template<class T>
ll stoi(T &str){
    ll ret;
    stringstream ss;
    ss << str;
    ss >> ret;
    return ret;
}
 
template<class T>
string toString(T i) {
    stringstream ss;
    ss << i;
    return ss.str();
}
 
struct prepare {
    prepare() {
        cout.setf(ios::fixed, ios::floatfield);
        cout.precision(8);
        ios_base::sync_with_stdio(false);
    }
} _prepare;
 
 
ll getNumOb1Str(ll num){
    ll counter=0;
    string str=toString(num);
    for(int i=0;i<str.size();i++){
        if(str.at(i)=='1')counter++;
    }
    return counter;
}
 
template<class T>
T getNumOb1(T num){
    T counter=0;
    for(T i=1;i<=num;i++){
        counter+=getNumOb1Str(i);
    }
    return counter;
}
 
 
int main() {
    string s;
    cin>>s;
    ll i=stoi(s);
    ll ans=getNumOb1(i);
    cout<<ans<<endl;
    return 0;
}