#include #include using namespace std; struct BigInt{ string val; BigInt():val("0"){} BigInt(string s){ if(s == "0"){ val = "0"; return; } bool firstdigit = false; for(int i = 0; s.size() > i; i++){ if('0' <= s[i] && s[i] <= '9'){ if(!firstdigit && s[i] == '0')continue; firstdigit = true; val.push_back(s[i]); }else if(s[i] == '-' && val.empty()){ val.push_back(s[i]); }else{ val = "0"; break; } } } BigInt abs(BigInt p){ if(p.val[0] == '-'){ p.val = p.val.substr(1,p.val.size()-1); } return p; } BigInt SignTurn(BigInt p){ if(p.val[0] == '-'){ p.val = p.val.substr(1,p.val.size()-1); }else{ p.val = "-" + p.val; } return p; } BigInt max(BigInt a,BigInt b){ if(a.val.size() > b.val.size()){ return a; }else if(a.val.size() < b.val.size()){ return b; }else{ for(int i = 0; a.val.size()> i; i++){ if(a.val[i] > b.val[i]){ return a; } if(a.val[i] < b.val[i]){ return b; } } } return a; } BigInt operator+=(const BigInt &p){ BigInt z = *this; BigInt k = p; if(z.val[0] == '-' && p.val[0] == '-'){ return SignTurn(abs(z)+abs(k));//(-123)+(-124) -> -((123)+(124)) }else if(z.val[0] == '-'){ return k-abs(z);//(-123)+(124) -> (124)-(123) }else if(p.val[0] == '-'){ return (z)-abs(k);//(123)+(-124) -> (123)-(124) }else{ //123 + 1234 bool Mvup = false; string ret = ""; if(z.val.size() < k.val.size()){ swap(z,k); } //val.size() > k.val.size(); for(int i = z.val.size()-1; 0 <= i; i--){ if(z.val.size()-k.val.size() > i){ //val[i]+Mvup ret.push_back(((z.val[i]-'0'+(Mvup?1:0))%10)+'0'); Mvup = ((z.val[i]-'0'+(Mvup?1:0))>=10); }else{ //val[i],k.val[i-(val.size()-k.val.size())]+Mvup ret.push_back(((z.val[i]-'0'+k.val[i-(z.val.size()-k.val.size())]-'0'+(Mvup?1:0))%10)+'0'); Mvup = ((z.val[i]-'0'+k.val[i-(z.val.size()-k.val.size())]-'0'+(Mvup?1:0)) >= 10); } } if(Mvup)ret.push_back('1'); reverse(ret.begin(),ret.end()); if(ret.empty())ret.push_back('0'); z.val = ret; } return z; } BigInt operator-=(const BigInt &p){ BigInt z = *this; BigInt k = p; if(z.val[0] == '-' && k.val[0] == '-'){ return (z)+abs(k);//(-123)-(-123) -> (-123)+(123) }else if(z.val[0] == '-'){ return (z)+SignTurn(k);//(-123)-(123) -> (-123)+(-123) }else if(k.val[0] == '-'){ return abs(k)+(z);//(123)-(-123) -> (123)+(123) }else{ string ret = ""; //z >= k bool Mvdwn = false; bool minus = false; if(max((z),k) != z){ minus = true; swap(z,k); } for(int i = z.val.size()-1; 0 <= i; i--){ if(z.val.size() - k.val.size() > i){ if(z.val[i]-'0' < (Mvdwn?1:0)){ ret.push_back(10+z.val[i]-(Mvdwn?1:0)); Mvdwn = true; }else{ ret.push_back(z.val[i]-(Mvdwn?1:0)); Mvdwn = false; } }else{ if(z.val[i] < k.val[i-(z.val.size()-k.val.size())]+(Mvdwn?1:0)){ ret.push_back(10+z.val[i]-(k.val[i-(z.val.size()-k.val.size())]+(Mvdwn?1:0)) + '0'); Mvdwn = true; }else{ ret.push_back(z.val[i]- (k.val[i-(z.val.size()-k.val.size())]+(Mvdwn?1:0)) + '0'); Mvdwn = false; } } } while(ret[ret.size()-1] == '0' && ret.size() > 1)ret.pop_back(); if(minus)ret.push_back('-'); if(ret.empty())ret.push_back('0'); reverse(ret.begin(),ret.end()); z.val = ret; } return z; } BigInt operator*=(const BigInt &p){ BigInt z = *this; BigInt k = p; bool hugo = false; if((z.val[0] == '-') + (p.val[0] == '-') == 1)hugo = true; z = abs(z);k = abs(k); } BigInt operator+(const BigInt &p){return (*this) += p;} BigInt operator-(const BigInt &p){return (*this) -= p;} bool operator==(const BigInt &p){return val == p.val;} bool operator!=(const BigInt &p){return val != p.val;} string retst(){ return val; } friend ostream &operator<<(ostream &os, const BigInt &p){ return os << p.val; } friend istream &operator>>(istream &is, BigInt &p){ string s; cin>>s; p = BigInt(s); return (is); } }; int main(){ BigInt z("1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283848586878889909192939495969798991"); int n;cin>>n; BigInt x("0"); for(int i = 0; n > i; i++){ x = x+z; } string s = x.retst(); if(190 == s.size()){ cout << "0."; } for(int i = 0; s.size() > i; i++){ cout << s[i]; if(s.size()-i-1 == 190)cout << "."; } cout << endl; }