52 lines
1.1 KiB
C++
52 lines
1.1 KiB
C++
#include<cstdio>
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#include<cstring>
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#include<cmath>
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char s[1010];
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char ans[1020];
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int st[1010][20];
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int Min(int x,int y)
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{
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return s[x] <= s[y] ? x : y;
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}
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void RMQ_Init(int len)
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{
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for(int i = 0; i < len; i++)
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st[i][0] = i;
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for(int j = 1; (1<<j) < len; j++)
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for(int i = 0; i+(1<<j)-1 < len;i++)
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st[i][j] = Min(st[i][j-1],st[i+(1<<(j-1))][j-1]);
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}
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int Query(int l,int r)
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{
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int k = (int)(log((double)(r-l+1))/log(2.0));
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return Min(st[l][k],st[r-(1<<k)+1][k]);
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}
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int main()
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{
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int len, m, i;
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while(scanf("%s%d",s, &m)!=EOF)
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{
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len = strlen(s);
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RMQ_Init(len);
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m = len - m;
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int pos = 0, num = 0;
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while(m--)
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{
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pos = Query(pos, len - m - 1);
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ans[num++] = s[pos++];
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}
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for(i = 0; i < num; i++)
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if(ans[i]!='0')
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break;
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if(i == num)
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printf("0");
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else
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{
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while(i < num)
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printf("%c",ans[i++]);
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}
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puts("");
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}
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return 0;
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}
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