【链接】 我是链接,点我呀:)
【题意】
题意
【题解】
设pre[i]表示i往前一直递增能递增多远
设aft[i]表示i往后一直递增能递增多远
如果aft[l]+pre[r]>=(r-l+1)那么就ok否则no
【代码】
import java.io.*;
import java.util.*;
public class Main {
static InputReader in;
static PrintWriter out;
public static void main(String[] args) throws IOException{
//InputStream ins = new FileInputStream("E:\\rush.txt");
InputStream ins = System.in;
in = new InputReader(ins);
out = new PrintWriter(System.out);
//code start from here
new Task().solve(in, out);
out.close();
}
static int N = 50000;
static class Task{
int n,m;
public void solve(InputReader in,PrintWriter out) {
n = in.nextInt();m = in.nextInt();
int a[] = new int[n+5];
int aft[] = new int[n+5],pre[] = new int[n+5];
for (int i = 1;i <= n;i++) a[i] = in.nextInt();
for (int i = n;i >= 1;i--) {
if (i+1<=n && a[i]<=a[i+1])
aft[i] = aft[i+1]+1;
else
aft[i] = 1;
}
for (int i = 1;i <= n;i++) {
if (i-1>=1 && a[i-1]>=a[i])
pre[i] = pre[i-1]+1;
else
pre[i] = 1;
}
for (int i = 1;i <= m;i++) {
int x,y;
x = in.nextInt();y = in.nextInt();
if (aft[x]+pre[y]>=(y-x+1)) {
System.out.println("Yes");
}else {
System.out.println("No");
}
}
}
}
static class InputReader{
public BufferedReader br;
public StringTokenizer tokenizer;
public InputReader(InputStream ins) {
br = new BufferedReader(new InputStreamReader(ins));
tokenizer = null;
}
public String next(){
while (tokenizer==null || !tokenizer.hasMoreTokens()) {
try {
tokenizer = new StringTokenizer(br.readLine());
}catch(IOException e) {
throw new RuntimeException(e);
}
}
return tokenizer.nextToken();
}
public int nextInt() {
return Integer.parseInt(next());
}
}
}