需求:单点更新,区间最值。
#include <algorithm> #include <iostream> #include <fstream> #include <sstream> #include <iomanip> #include <map> #include <set> #include <list> #include <stack> #include <queue> #include <deque> #include <vector> #include <string> #include <bitset> #include <memory> #include <complex> #include <numeric> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <math.h> #include <time.h> #include <ctype.h> #include <locale.h> using namespace std; #pragma pack(4) const double eps = 1e-8; const double pi = acos(-1.0); const int inf = 0x7f7f7f7f; #define loop(a,n) \ for(int i=0;n>i;i++) \ cout<<a[i]<<(i!=n-1?' ':'\n') #define loop2(a,n,m) \ for(int i=0;n>i;i++) \ for(int j=0;m>j;j++) \ cout<<a[i][j]<<(j!=m-1?' ':'\n') #define at(a,i) ((a)&(1<<(i))) #define nt(a,i) ((a)^(1<<(i))) #define set1(a,i) ((a)|(1<<(i))) #define set0(a,i) ((a)&(~(1<<(i)))) #define gret(a,b) (((a)-(b))>eps) #define less(a,b) (((b)-(a))>eps) #define greq(a,b) (((a)-(b))>-eps) #define leeq(a,b) (((b)-(a))>-eps) #define equl(a,b) (fabs((a)-(b))<eps) #define lmax(a,b) ((a)>(b)?(a):(b)) #define lmin(a,b) ((a)<(b)?(a):(b)) #define fmax(a,b) (gret(a,b)?(a):(b)) #define fmin(a,b) (less(a,b)?(a):(b)) const int MAXV = 50002; namespace ST { int left,right,up[MAXV<<2],down[MAXV<<2]; #define lc(i) ((i)<<1) #define rc(i) ((i)<<1|1) void clear(int l,int r) { left=l; right=r; memset(up,0,sizeof(up)); memset(down,inf,sizeof(up)); } void change(int x,int w,int l=left,int r=right,int i=1) { if(l==x&&x==r) { up[i]=max(up[i],w); down[i]=min(down[i],w); } else { if(x<=(l+r)/2) change(x,w,l,(l+r)/2,lc(i)); if((l+r)/2<x) change(x,w,(l+r)/2+1,r,rc(i)); up[i]=max(up[lc(i)],up[rc(i)]); down[i]=min(down[lc(i)],down[rc(i)]); } } int query_up(int x,int y,int l=left,int r=right,int i=1) { if(x<=l&&r<=y) return up[i]; else { int cnt=0; if(x<=(l+r)/2) cnt=max(cnt,query_up(x,y,l,(l+r)/2,lc(i))); if((l+r)/2<y) cnt=max(cnt,query_up(x,y,(l+r)/2+1,r,rc(i))); return cnt; } } int query_down(int x,int y,int l=left,int r=right,int i=1) { if(x<=l&&r<=y) return down[i]; else { int cnt=inf; if(x<=(l+r)/2) cnt=min(cnt,query_down(x,y,l,(l+r)/2,lc(i))); if((l+r)/2<y) cnt=min(cnt,query_down(x,y,(l+r)/2+1,r,rc(i))); return cnt; } } int query(int x,int y) { return query_up(x,y)-query_down(x,y); } } int n,m,w,x,y; int main() { #ifndef ONLINE_JUDGE freopen("Balanced Lineup.txt","r",stdin); #endif while(scanf("%d %d",&n,&m)!=EOF) { ST::clear(1,n); for(int i=1;n>=i;i++) { scanf("%d",&w); ST::change(i,w); } for(int i=1;m>=i;i++) { scanf("%d %d",&x,&y); printf("%d\n",ST::query(x,y)); } } return 0; }