【习题 8-4 UVA - 11491】Erasing and Winning

/*
    1.Shoud it use long long ?
    2.Have you ever test several sample(at least therr) yourself?
    3.Can you promise that the solution is right? At least,the main ideal
    4.use the puts("") or putchar() or printf and such things?
    5.init the used array or any value?
    6.use error MAX_VALUE?
    7.use scanf instead of cin/cout?
    8.whatch out the detail input require
*/
/*
    一定在这里写完思路再敲代码!!!
*/
#include <bits/stdc++.h>
using namespace std;

const int N = 1e5;

int n,d,l[N+10],r[N+10];
char s[N+10];

void sc(int x){
    int L = l[x],R = r[x];
    r[L] = R;
    l[R] = L;
}

int main(){
    #ifdef LOCAL_DEFINE
        freopen("rush_in.txt", "r", stdin);
    #endif
    ios::sync_with_stdio(0),cin.tie(0);
    while (cin >> n >> d && n && d){
        cin >> (s+1);
        for (int i = 0;i <= n;i++)
            l[i] = i-1,r[i] = i+1;
        int now = r[0];
        while (1){
            if (d==0)break;
            int nex = r[now];
            while (nex <= n && s[nex]<=s[now]){
                now = r[now];
                nex  = r[nex];
            }
            sc(now);
            now = l[now];
            if (now==0) now = r[now];
            d--;
        }
        for (int i = r[0];i!=n+1;i=r[i])
            cout << s[i];
        cout << endl;
    }
    return 0;
}