简单题，求一定范围内的最大数于最小数之差，用两个数组保存max和min就行了。

1 #include 
     
       2 #include 
      
        3 #define N 50005 4 #define INF 0x7fffffff 5 int max[4*N],min[4*N]; 6 int D; 7 int Max(int a,int b) 8 { 9     return a>b ?a :b;10 }11 int Min(int a,int b)12 {13     return a
       >=1, j>>=1)20     {21         if(~i & 1)22             mi = Min(mi,min[i^1]),23             ma = Max(ma,max[i^1]);24         if(j & 1)25             mi = Min(mi,min[j^1]),26             ma = Max(ma,max[j^1]);27     }28     return ma-mi;29 }30 int main()31 {32     int m,n,i,x,y;33     while(~scanf("%d%d",&n,&m))34     {35         for(D = 1; D < n+2; D <<= 1);36         memset(max,0xc3,sizeof(int)*2*D);37         memset(min,0x3f,sizeof(int)*2*D);38         for(i = 1; i <= n; i++)39         {40             scanf("%d",&max[D+i]);41             min[D+i] = max[D+i];42         }43         for(i = D-1; i; i--)44         {45             max[i] = Max(max[i<<1],max[i<<1|1]);46             min[i] = Min(min[i<<1],min[i<<1|1]);47         }48         while(m--)49         {50             scanf("%d%d",&x,&y);51             printf("%d\n",query(x,y));52         }53     }54     return 0;55 }