POJ--3386--Frequent values--RMQ

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贴完代码就滚，杭州邀请赛被虐的节奏-_-#

#include<iostream>#include<cstring>#include<cstdio>#define maxn 100200using namespace std;int num[maxn],ic,last_num;int pos[maxn];int a[maxn],n;int sum[maxn];int x,y,m;int dp[maxn][20];bool init(){    ic=0;last_num=10000000;    scanf("%d",&n);    if(n==0)return 0;    scanf("%d",&m);    memset(num,0,sizeof(num));    memset(sum,0,sizeof(sum));    for(int i=1;i<=n;i++)    {        scanf("%d",&a[i]);        if(a[i]!=last_num)        {            ++ic;            num[ic]++;            last_num=a[i];        }        else        {            num[ic]++;        }        pos[i]=ic;    }    for(int i=1;i<=ic;i++)sum[i]=num[i]+sum[i-1];    return 1;}void RMQ_init(){    memset(dp,0,sizeof(dp));    for(int i=1;i<=ic;i++)    dp[i][0]=num[i];    for(int j=1;(1<<j)<=ic;j++)    {        for(int i=1;i+(1<<j)-1<=ic;i++)        {            dp[i][j]=max(dp[i][j-1],dp[i+(1<<(j-1))][j-1]);        }    }}int RMQ(int a,int b){    int len=0;    while(a+(1<<(len+1))-1<=b)len++;    return max(dp[a][len],dp[b-(1<<len)+1][len]);}void solve(){    int p1,p2,temp;    RMQ_init();    for(int i=0;i<m;i++)    {        scanf("%d%d",&x,&y);        if(x>y)swap(x,y);        p1=pos[x];        p2=pos[y];        if(p1!=p2)        temp=max(sum[p1]-x+1,y-sum[p2-1]);        else        temp=y-x+1;        if(p1+1<=p2-1)        {            temp=max(temp,RMQ(p1+1,p2-1));        }        printf("%d\n",temp);    }}int main(){    //freopen("3286.in","r",stdin);    while(init())    solve();    return 0;}