您的位置:首页 > 其它

Codeforces 777C-Alyona and Spreadsheet

2017-02-25 21:34 435 查看
Alyona and Spreadsheet

time limit per test
1 second

memory limit per test
256 megabytes

input
standard input

output
standard output

During the lesson small girl Alyona works with one famous spreadsheet computer program and learns how to edit tables.

Now she has a table filled with integers. The table consists of n rows and m columns.
By ai, j we
will denote the integer located at the i-th row and the j-th
column. We say that the table is sorted in non-decreasing order in the column j if ai, j ≤ ai + 1, j for
all i from 1 to n - 1.

Teacher gave Alyona k tasks. For each of the tasks two integers l and r are
given and Alyona has to answer the following question: if one keeps the rows from l to r inclusive
and deletes all others, will the table be sorted in non-decreasing order in at least one column? Formally, does there exist such j that ai, j ≤ ai + 1, j for
all i from l to r - 1 inclusive.

Alyona is too small to deal with this task and asks you to help!

Input

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).

Output

Print "Yes" to the i-th line of
the output if the table consisting of rows from li to ri inclusive
is sorted in non-decreasing order in at least one column. Otherwise, print "No".

Example

input
5 4
1 2 3 5
3 1 3 2
4 5 2 3
5 5 3 2
4 4 3 4
6
1 1
2 5
4 5
3 5
1 3
1 5


output
Yes
No
Yes
Yes
Yes
No


Note

In the sample, the whole table is not sorted in any column. However, rows 1–3 are sorted in column 1, while rows 4–5 are sorted in column 3.

题意:给出n*m的矩阵,k次查询,如果第l行到r行至少有一列是非递减的,则输出Yes,否则输出No

解题思路:预处理每行能到达最大行是多少,把每列能到达的最大行保存一下

#include <iostream>
#include <cstdio>
#include <string>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <queue>
#include <vector>
#include <set>
#include <stack>
#include <map>
#include <climits>

using namespace std;
#define LL long long

int c[100009],d[100009];

int main()
{
int n,m;
while(~scanf("%d%d",&n,&m))
{
int a[n+10][m+10];
for (int i=1; i<=n; i++)
for (int j=1; j<=m; j++)
scanf("%d",&a[i][j]);
memset(c,0,sizeof c);
memset(d,0,sizeof d);
for (int i=1; i<=n; i++)
{
for (int j=1; j<=m; j++)
{
int k=max(i,d[j]);
while(a[k+1][j]>=a[k][j]&&k<n) k++;
d[j]=k;
c[i]=max(k,c[i]);
}
}
int q,l,r;
scanf("%d",&q);
while(q--)
{
scanf("%d %d",&l,&r);
if(c[l]>=r) printf("Yes\n");
else printf("No\n");
}
}
return 0;
}
内容来自用户分享和网络整理,不保证内容的准确性,如有侵权内容,可联系管理员处理 点击这里给我发消息
标签: