【分块】BZOJ4216 Pig

题面在这里

典型的分块题……

没什么好说的，直接分块搞就好了

示例程序：

#include<cstdio>
#include<cmath>
#include<algorithm>
#define _abs(x) ((x)<0?-(x):(x))
#define LL long long
using namespace std;

const int maxn=500005;
int n,q,t,a[maxn],blk;
LL sum[710];
int main(){
    scanf("%d%d%d",&n,&q,&t);
    blk=sqrt(n);
    for (int i=1;i<=n;i++)
     scanf("%d",&a[i]),sum[i/blk]+=a[i];
    LL lastans=0;
    for (int i=1;i<=q;i++){
        int l,r;scanf("%d%d",&l,&r);
        if (t==1){
            l=(l^_abs(lastans))%n+1;
            r=(r^_abs(lastans))%n+1;
            if (l>r) swap(l,r);
        }
        int bl=l/blk,br=r/blk;LL ans=0;
        if (bl==br){
            for (int j=l;j<=r;j++) ans+=a[j];
        }else{
            for (int j=l,tj=(bl+1)*blk;j<tj;j++) ans+=a[j];
            for (int j=br*blk;j<=r;j++) ans+=a[j];
            for (int j=bl+1;j<br;j++) ans+=sum[j];
        }
        printf("%lld\n",ans);lastans=ans;
    }
    return 0;
}