2738: 矩阵乘法 整体二分+树状数组

水一发，和区间k小基本一样，不过这个无修改。感觉有修改会很麻烦？

#include<iostream>#include<cstdio>#include<vector>#include<algorithm>#define inf 1000000007using namespace std;int n,Q,now,cnt;int tree[505][505];struct node {int x,y,z;} a[250005];int ans[60005];struct query {int x1,x2,y1,y2,k,id;} q[60005],q1[60005],q2[60005];inline int read(){    int a=0,f=1; char c=getchar();    while (c<'0'||c>'9') {if (c=='-') f=-1; c=getchar();}    while (c>='0'&&c<='9') {a=a*10+c-'0'; c=getchar();}    return a*f;}inline int lowbit(int i){    return i&(-i);}inline bool operator<(node a,node b){    return a.z<b.z;}inline void add(int x,int y,int val){    for (int i=x;i<=n;i+=lowbit(i))        for (int j=y;j<=n;j+=lowbit(j))            tree[i][j]+=val;}inline int query(int x,int y){    int tmp=0;    for (int i=x;i;i-=lowbit(i))        for (int j=y;j;j-=lowbit(j))            tmp+=tree[i][j];    return tmp;}void solve(int t,int w,int l,int r){    if (t>w) return;    if (l==r)    {        for (int i=t;i<=w;i++) ans[q[i].id]=l;        return;    }    int mid=l+r>>1;    while (a[now].z<=mid) now++,add(a[now].x,a[now].y,1);    while (a[now].z>mid) add(a[now].x,a[now].y,-1),now--;    int p1=0,p2=0;    for (int i=t;i<=w;i++)    {        int tmp=query(q[i].x2,q[i].y2)+query(q[i].x1-1,q[i].y1-1)-query(q[i].x1-1,q[i].y2)-query(q[i].x2,q[i].y1-1);        if (tmp>q[i].k-1) q1[++p1]=q[i]; else q2[++p2]=q[i];    }    for (int i=1;i<=p1;i++) q[t+i-1]=q1[i];    for (int i=1;i<=p2;i++) q[t+p1+i-1]=q2[i];    solve(t,t+p1-1,l,mid); solve(t+p1,w,mid+1,r);}int main(){    n=read(); Q=read();    for (int i=1;i<=n;i++)        for (int j=1;j<=n;j++)            a[++cnt].x=i,a[cnt].y=j,a[cnt].z=read();    sort(a+1,a+cnt+1);    a[++cnt].x=1; a[cnt].y=1; a[cnt].z=inf;    for (int i=1;i<=Q;i++)        q[i].x1=read(),q[i].y1=read(),q[i].x2=read(),q[i].y2=read(),q[i].k=read(),q[i].id=i;    solve(1,Q,0,inf);    for (int i=1;i<=Q;i++) printf("%d\n",ans[i]);    return 0;}