题意:给你一个n*m的数阵 对于一行到另一行,若存在一列从上到下递减,则称之符合题意
The first line of the input contains two positive integers n and m (1 ≤ n·m ≤ 100 000) — the number of rows and the number of columns in the table respectively. Note that your are given a constraint that bound the product of these two integers, i.e. the number of elements in the table.
Each of the following n lines contains m integers. The j-th integers in the i of these lines stands for ai, j (1 ≤ ai, j ≤ 109).
The next line of the input contains an integer k (1 ≤ k ≤ 100 000) — the number of task that teacher gave to Alyona.
The i-th of the next k lines contains two integers li and ri (1 ≤ li ≤ ri ≤ n).
以上是数据范围
a【】来存储每一行的数
b【】来存储每一列能到达的最上行
在用c【】来存储每一行能到达的最上行
#include<cstdio>
using namespace std;
int a[100005],b[100005],c[100005];
int main()
{
int n,m,x,i,j,r,l,k;
scanf("%d%d",&n,&m);
for(i=1;i<=m;i++)
b[i]=1;
for(i=1;i<=n;i++){
c[i]=i;
for(j=1;j<=m;j++){
scanf("%d",&x);
if(x<a[j])
b[j]=i;
a[j]=x;
if(b[j]<c[i])
c[i]=b[j];
}
}
scanf("%d",&k);
while(k--){
scanf("%d%d",&r,&l);
if(c[l]<=r)
printf("Yes
");
else
printf("No
");
}
return 0;
}
。
思路:由于有多次询问所以先打表,记录每一行所能到达的最上行即可