算法模板——线段树3（区间覆盖值+区间求和）

 1 var
 2    i,j,k,l,m,n,a1,a2,a3,a4:longint;
 3    a,b,d:array[0..100000] of longint;
 4 function max(x,y:longint):longint;inline;
 5          begin
 6               if x>y then max:=x else max:=y;
 7          end;
 8 function min(x,y:longint):longint;inline;
 9          begin
10               if x<y then min:=x else min:=y;
11          end;
12 procedure ext(z,x,y:longint);inline;
13           begin
14                if d[z]=0 then exit;
15                a[z]:=b[z]*(y-x+1);
16                if x<>y then
17                   begin
18                        b[z*2]:=b[z];d[z*2]:=1;
19                        b[z*2+1]:=b[z];d[z*2+1]:=1;
20                   end;
21                b[z]:=0;d[z]:=0;
22           end;
23 function op(z,x,y,l,r,p:longint):longint;inline;
24          var a3,a4:longint;
25          begin
26               if l>r then exit(0);
27               if (x=l) and (y=r) then
28                  begin
29                       if d[z]=1 then a[z]:=b[z]*(r-l+1);
30                       d[z]:=1;b[z]:=p;
31                       exit(p*(r-l+1)-a[z]);
32                  end;
33               ext(z,x,y);
34               a3:=op(z*2,x,(x+y) div 2,l,min(r,(x+y) div 2),p);
35               a4:=op(z*2+1,(x+y) div 2+1,y,max((x+y) div 2+1,l),r,p);
36               a[z]:=a[z]+a3+a4;
37               exit(a3+a4);
38          end;
39 function cal(z,x,y,l,r:longint):longint;inline;
40          begin
41               if l>r then exit(0);
42               if d[z]=1 then exit(b[z]*(r-l+1));
43               if (x=l) and (y=r) then exit(a[z]);
44               exit(cal(z*2,x,(x+y) div 2,l,min(r,(x+y) div 2))+cal(z*2+1,(x+y) div 2+1,y,max(l,(x+y) div 2+1),r));
45          end;
46 procedure built(z,x,y:longint);inline;
47           begin
48                if x=y then
49                   read(a[z])
50                else
51                    begin
52                         built(z*2,x,(x+y) div 2);
53                         built(z*2+1,(x+y) div 2+1,y);
54                         a[z]:=a[z*2]+a[z*2+1];
55                    end;
56                b[z]:=0;d[z]:=0;
57           end;
58 begin
59      readln(n,m);
60      built(1,1,n);
61      readln;
62      for i:=1 to m do
63          begin
64               read(j);
65               case j of
66                    1:begin
67                           readln(a1,a2,a3);
68                           op(1,1,n,a1,a2,a3);
69                    end;
70                    2:begin
71                           readln(a1,a2);
72                           writeln(cal(1,1,n,a1,a2));
73                    end;
74                    else halt;
75               end;
76          end;
77 end.
78