裸的主席树，没什么好说的
1 type node=record 2 l,r,s:longint; 3 end; 4 var tree:array[0..2000010] of node; 5 sa,rank,a,b,sum,head:array[0..100010] of longint; 6 t,k,x,y,i,n,m,p:longint; 7 8 procedure swap(var a,b:longint); 9 var c:longint; 10 begin 11 c:=a; 12 a:=b; 13 b:=c; 14 end; 15 16 procedure sort(l,r: longint); 17 var i,j,x:longint; 18 begin 19 i:=l; 20 j:=r; 21 x:=a[(l+r) shr 1]; 22 repeat 23 while a[i]<x do inc(i); 24 while x<a[j] do dec(j); 25 if not(i>j) then 26 begin 27 swap(a[i],a[j]); 28 swap(b[i],b[j]); 29 inc(i); 30 j:=j-1; 31 end; 32 until i>j; 33 if l<j then sort(l,j); 34 if i<r then sort(i,r); 35 end; 36 37 procedure update(x:longint); 38 begin 39 tree[x].s:=tree[tree[x].l].s+tree[tree[x].r].s; 40 end; 41 42 function build(l,r:longint):longint; 43 var m,q:longint; 44 begin 45 inc(t); 46 q:=t; 47 if l=r then exit(t) 48 else begin 49 m:=(l+r) shr 1; 50 tree[q].l:=build(l,m); 51 tree[q].r:=build(m+1,r); 52 end; 53 exit(q); 54 end; 55 56 function pre(w,l,r:longint):longint; 57 var m,q:longint; 58 begin 59 inc(t); 60 q:=t; 61 if l=r then 62 tree[q].s:=sum[l] 63 else begin 64 m:=(l+r) shr 1; 65 if rank[i]<=m then 66 begin 67 tree[q].l:=pre(tree[w].l,l,m); 68 tree[q].r:=tree[w].r; 69 end 70 else begin 71 tree[q].l:=tree[w].l; 72 tree[q].r:=pre(tree[w].r,m+1,r); 73 end; 74 update(q); 75 end; 76 exit(q); 77 end; 78 79 function ask(x,y,l,r:longint):longint; 80 var m,a,b:longint; 81 begin 82 if l=r then 83 exit(sa[l]) 84 else begin 85 m:=(l+r) shr 1; 86 a:=tree[x].l; 87 b:=tree[y].l; 88 // writeln(l,' ',m,' ',tree[b].s-tree[a].s); 89 if tree[b].s-tree[a].s>=k then 90 exit(ask(a,b,l,m)) 91 else begin 92 k:=k-(tree[b].s-tree[a].s); 93 exit(ask(tree[x].r,tree[y].r,m+1,r)); 94 end; 95 end; 96 end; 97 98 begin 99 readln(n,m); 100 for i:=1 to n do 101 begin 102 read(a[i]); 103 b[i]:=i; 104 end; 105 sort(1,n); 106 p:=1; 107 rank[b[1]]:=1; 108 sa[1]:=a[1]; 109 for i:=2 to n do 110 begin 111 if a[i]<>a[i-1] then 112 begin 113 inc(p); 114 sa[p]:=a[i]; 115 end; 116 rank[b[i]]:=p; 117 end; 118 t:=0; 119 head[0]:=build(1,p); 120 for i:=1 to n do 121 begin 122 inc(sum[rank[i]]); 123 head[i]:=pre(head[i-1],1,p); 124 end; 125 for i:=1 to m do 126 begin 127 readln(x,y,k); 128 writeln(ask(head[x-1],head[y],1,p)); 129 end; 130 end.