#include<stdio.h>
#define MAX_N 50000+16
#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1
#define min(x,y) ((x>y)?(y):(x))
#define max(x,y) ((x>y)?(x):(y))
#define INF 0x3f3f3f3f
int N,Q;
int t1[MAX_N<<2],d[MAX_N],t2[MAX_N<<2];
void build(int l,int r,int rt)
{
int m;
if(l==r)
{
scanf("%d",&t1[rt]);
t2[rt]=t1[rt];
return ;
}
m=(l+r)>>1;
build(lson);
build(rson);
t1[rt]=min(t1[rt<<1],t1[rt<<1|1]);
t2[rt]=max(t2[rt<<1],t2[rt<<1|1]);
}
int query1(int a,int b,int l,int r,int rt)
{
int res,res1,res2,m;
if(a<=l&&r<=b)
{
return t1[rt];
}
if(b<l||a>r)
return INF;
m=(l+r)>>1;
res1=query1(a,b,lson);
res2=query1(a,b,rson);
res=min(res1,res2);
return res;
}
int query2(int a,int b,int l,int r,int rt)
{
int res,res1,res2,m;
if(a<=l&&r<=b)
{
return t2[rt];
}
if(b<l||a>r)
return 0;
m=(l+r)>>1;
res1=query2(a,b,lson);
res2=query2(a,b,rson);
res=max(res1,res2);
return res;
}
int main()
{
int i,a,b;
scanf("%d%d",&N,&Q);
build(1,N,1);
for(i=1;i<=Q;i++)
{
scanf("%d%d",&a,&b);
printf("%d\n",query2(a,b,1,N,1)-query1(a,b,1,N,1));
}
}
poj 3264 Balanced Lineup(线段树)
最新推荐文章于 2023-10-07 08:26:33 发布