C :

int main(int argc, char* argv[])
{char f[2];
int a,b,i,score[30001],N,M,max;

while(~scanf("%d%d",&N,&M))
{
	for(i=1;i<=N;i++)
       scanf("%d",&score[i]);
while(M--)
{scanf("%s%d%d",&f,&a,&b);
max=0;
if(f[0]=='Q'){
	max=score[a];
	for(i=a+1;i<=b;i++)
		if(score[i]>max)max=score[i];
printf("%d\n",max);
}
else if(f[0]=='U')	
{
score[a]=b;
}	
}
}
	return 0;
}

C++ :

#include<cstdio>
#include<algorithm>
using namespace std;

#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1

const int maxn=222222;
int MAX[maxn<<2];

void PushUP(int rt)
{
	MAX[rt]=max(MAX[rt<<1],MAX[rt<<1|1]);
}

void build(int l,int r,int rt)
{
	if(l==r)
	{
		scanf("%d",&MAX[rt]);
		return ;
	}
	int m=(l+r)>>1;
	build(lson);
	build(rson);
	PushUP(rt);
}

void update(int p,int sc,int l,int r,int rt)
{
	if(l==r)
	{
		MAX[rt]=sc;
		return ;
	}
	int m=(l+r)>>1;
	if(p<=m)
		update(p,sc,lson);
	else
		update(p,sc,rson);
	PushUP(rt);
}

int query(int L,int R,int l,int r,int rt)
{
	if(L<=l&&r<=R)
	{
		return MAX[rt];
	}
	int m=(l+r)>>1;
	int ret=0;
	if(L<=m)
		ret=max(ret,query(L,R,lson));
	if(R>m)
		ret=max(ret,query(L,R,rson));
	return ret;
}

int main()
{
	int n,m;
	while(scanf("%d%d",&n,&m)!=EOF)
	{
		build(1,n,1);
		while(m--)
		{
			char op[2];
			int a,b;
			scanf("%s%d%d",op,&a,&b);
			if(op[0]=='Q')
				printf("%d\n",query(a,b,1,n,1));
			else
				update(a,b,1,n,1);
		}
	}
	return 0;
}

Java :

import java.util.*;
public class Main{
    public static void main(String[] args){
        Scanner in=new Scanner(System.in);
        while(in.hasNextInt()){
        int n=in.nextInt();
        int m=in.nextInt();
        int mark[]=new int[n];
        int a,b;
        for(int i=0;i<n;i++)
            mark[i]=in.nextInt();
        for(int j=1;j<=m;j++){
           String c=in.next();
           char s=c.charAt(0);
           if(s=='Q') {
                a =in.nextInt()-1;
                b =in.nextInt()-1;
               int max=mark[a];
               for(int k=a+1;k<=b;k++)
                   if(mark[k]>max) max=mark[k];
               System.out.println(max);
            }
            if(s=='U') {
                a =in.nextInt();
                b =in.nextInt();
                mark[a-1]=b;
            }
        }
    }
}
}