UVA - 11491 Erasing and Winning

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在满足要求的情况下找已经选出的答案。

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#include<iostream>#include<cstdio>#include<string>using namespace std;const int maxn = 1e5 + 5;int vis[maxn];int main(){    int n, d;    while(scanf("%d%d", &n, &d) == 2 && (n||d))    {        getchar();        int k = n-d;        int cnt = 0;        for(int i = 0; i < n; ++i)        {            int  kk  = getchar() - '0';            while(cnt && cnt+n-i > k && kk > vis[cnt-1]) --cnt;            if(cnt < k) vis[cnt++] = kk;        }        for(int i = 0; i < k; ++i) cout << vis[i];        cout << "\n";    }    return 0;}