USACO-T026: Preface Numbering

/*
ID: mickyta1
TASK: preface
LANG: C++
*/

#include <bits/stdc++.h>
using namespace std;

const int N = 7 + 5;

int np, ans[N];
char str[N] = "IVXLCDM";

void AddRoman(int n){
    int tmp;
    if(n / 1000 > 0){
        tmp = n / 1000;
        ans[6] += tmp;
        n %= 1000;
    }
    if(n / 100 > 0){
        tmp = n / 100;
        if(tmp == 9){
            ++ans[6];
            ++ans[4];
        } else if(tmp == 4){
            ++ans[5];
            ++ans[4];
        } else {
            if(tmp >= 5){
                ++ans[5];
                tmp -= 5;
            }
            ans[4] += tmp;
        }
        n %= 100;
    }
    if(n / 10 > 0){
        tmp = n / 10;
        if(tmp == 9){
            ++ans[4];
            ++ans[2];
        } else if(tmp == 4){
            ++ans[3];
            ++ans[2];
        } else {
            if(tmp >= 5){
                ++ans[3];
                tmp -= 5;
            }
            ans[2] += tmp;
        }
        n %= 10;
    }
    tmp = n;
    if(tmp == 9){
        ++ans[2];
        ++ans[0];
    } else if(tmp == 4){
        ++ans[1];
        ++ans[0];
    } else {
        if(tmp >= 5){
            ++ans[1];
            tmp -= 5;
        }
        ans[0] += tmp;
    }
    return;
}

int main(){
    freopen("preface.in", "r", stdin);
    freopen("preface.out", "w", stdout);

    scanf("%d", &np);
    for(int i = 1; i <= np; ++i){
        AddRoman(i);
    }
    int upb;
    for(upb = 6; upb >= 0; --upb){
        if(ans[upb] > 0){
            break;
        }
    }
    for(int i = 0; i <= upb; ++i){
        cout << str[i] << ' ' << ans[i] << '\n';
    }

    fclose(stdin);
    fclose(stdout);
    return 0;
}