Go: package main

// packed from [splaytree.go main.rmq.go splaytree_debug.go] with goone.

import (
	"bufio"
	"fmt"
	"io"
	"os"
	"strconv"
	"strings"
)

type SplayTreeNode struct {
	parent, left, right *SplayTreeNode

	size    int
	value   int
	minimum int
}

func newSplayTreeNode(v int) *SplayTreeNode {
	return &SplayTreeNode{value: v}
}

func (node *SplayTreeNode) rotate() {
	var pp, p, c *SplayTreeNode
	p = node.parent
	pp = p.parent
	if pp != nil && pp.left == p {
		pp.left = node
	}
	if pp != nil && pp.right == p {
		pp.right = node
	}
	node.parent = pp
	if p.left == node {
		c = node.right
		node.right = p
		p.left = c
	} else {
		c = node.left
		node.left = p
		p.right = c
	}
	p.parent = node
	if c != nil {
		c.parent = p
	}
	p.update()
	node.update()
}

func (node *SplayTreeNode) state() int {
	if node.parent == nil {
		return 0
	}
	if node.parent.left == node {
		return -1
	} else if node.parent.right == node {
		return 1
	}
	return 0
}

func (node *SplayTreeNode) splay() {
	for node.state() != 0 {
		if node.parent.state() == 0 {
			node.rotate()
			return
		}
		if node.state() == node.parent.state() {
			node.parent.rotate()
			node.rotate()
		} else {
			node.rotate()
			node.rotate()
		}
	}
}

func (node *SplayTreeNode) update() {
	node.size = 1
	node.minimum = node.value
	if node.left != nil {
		node.size += node.left.size
		node.minimum = min(node.minimum, node.left.minimum)
	}
	if node.right != nil {
		node.size += node.right.size
		node.minimum = min(node.minimum, node.right.minimum)
	}
}
func min(a, b int) int {
	if a < b {
		return a
	}
	return b
}

func (node *SplayTreeNode) Get(idx int) *SplayTreeNode {
	cur := node
	for true {
		lSize := 0
		if cur.left != nil {
			lSize = cur.left.size
		}
		if idx < lSize {
			cur = cur.left
		}
		if lSize == idx {
			cur.splay()
			return cur
		}
		if idx > lSize {
			cur = cur.right
			idx = idx - lSize - 1
		}
	}
	return nil
}

func mergeSplayNode(l, r *SplayTreeNode) (root *SplayTreeNode) {
	if l == nil {
		return r
	}
	if r == nil {
		return l
	}
	root = l.Get(l.size - 1)
	root.right = r
	r.parent = root
	root.update()
	return root
}

func (node *SplayTreeNode) Split(leftCount int) (left *SplayTreeNode, right *SplayTreeNode) {
	root := node.Get(leftCount)
	lRoot, rRoot := root.left, root

	rRoot.left = nil
	if lRoot != nil {
		lRoot.parent = nil
	}
	rRoot.update()
	return lRoot, rRoot
}

func splayTreeInsert(t *SplayTreeNode, idx int, node *SplayTreeNode) (root *SplayTreeNode) {
	l, r := t.Split(idx)
	return mergeSplayNode(
		mergeSplayNode(l, node),
		r,
	)
}

func removeSplayTree(t *SplayTreeNode, idx int) (root *SplayTreeNode, removed *SplayTreeNode) {
	target := t.Get(idx)
	l, r := target.left, target.right
	if l != nil {
		l.parent = nil
	}
	if r != nil {
		r.parent = nil
	}
	target.left = nil
	target.right = nil
	target.update()
	return mergeSplayNode(l, r), target
}

const (
	initialBufSize = 100000
	maxBufSize     = 1000000
)

var sc *bufio.Scanner

func initScanner(r io.Reader) *bufio.Scanner {
	buf := make([]byte, initialBufSize)

	sc := bufio.NewScanner(r)
	sc.Buffer(buf, maxBufSize)
	sc.Split(bufio.ScanWords)
	return sc
}

func main() {
	sc = initScanner(os.Stdin)
	resolve()
}

func resolve() {
	n := scanInt(sc)
	q := scanInt(sc)
	table := newDebugNodeSlice(200001)
	for i := 0; i < n; i++ {
		table.l[i].parent = &table.l[i+1]
		table.l[i+1].left = &table.l[i]
		table.l[i].update()
		table.l[i+1].update()
	}
	var root *SplayTreeNode = &table.l[n]
	for i := 0; i < n; i++ {
		table.l[i].value = scanInt(sc)
		table.l[i].update()
	}
	table.l[n].update()
	for i := 0; i < q; i++ {
		switch scanInt(sc) {
		case 0:
			root = shift(root, scanInt(sc), scanInt(sc))
		case 1:
			l := scanInt(sc)
			r := scanInt(sc)
			tmp, rRoot := root.Split(r + 1)
			lRoot, cRoot := tmp.Split(l)
			fmt.Println(cRoot.minimum)
			root = mergeSplayNode(mergeSplayNode(lRoot, cRoot), rRoot)
		case 2:
			root = root.Get(scanInt(sc))
			root.value = scanInt(sc)
			root.update()
		}
	}
}


C++: #include <iostream>
#include <algorithm>
#include <vector>
#include <cstdio>
#include <tr1/random>
using namespace std;

const int INF = 200000000;
tr1::mt19937 mt;

struct RBST{
	int count;
	int value;
	int minimum;
	RBST *l, *r;
	RBST(int value = 0):count(1), value(value), minimum(value), l(NULL), r(NULL){}
	static int size(RBST *a){
		return a ? a->count : 0;
	}
	static int get_min(RBST *a){
		return a ? a->minimum : INF;
	}
	RBST *update(){
		count = 1 + size(l) + size(r);
		minimum = min({get_min(l), get_min(r), value});
		return this;
	}
	// aとbを連結する(破壊的)
	static RBST *merge(RBST *a, RBST *b){
		if(!a || !b) return a?a:b;
		if( (int)(mt() % (size(a) + size(b))) < size(a)){ // aの方が優先度が高い
			a->r = merge(a->r, b);
			return a->update();
		}else{
			b->l = merge(a, b->l);
			return b->update();
		}
	}

	// [0,k)と[k,n)の2つの木に分割する
	static pair<RBST*,RBST*> split(RBST *a, int k){
		if(!a) return make_pair<RBST*,RBST*>(NULL, NULL);
		if(k <= size(a->l)){
			pair<RBST*,RBST*> t = split(a->l, k);
			a->l = t.second;
			return make_pair(t.first, a->update());
		}else{
			pair<RBST*,RBST*> t = split(a->r, k - size(a->l) - 1);
			a->r = t.first;
			return make_pair(a->update(), t.second);
		}
	}
};


RBST nodes[200000];
int p;
int x,y,z;
int main(){
	int n,k;
	scanf("%d%d",&n,&k);
	RBST *s;
	for(int i=0;i<n;i++){
		int a;
		scanf("%d", &a);
		nodes[p] = RBST(a);
		s = RBST::merge(s, &nodes[p++]);
	}
	for(;k--;){
		scanf("%d%d%d",&x,&y,&z);
		if(x==0){
			z++;
			auto t1 = RBST::split(s, y);
			auto t2 = RBST::split(t1.second, z - y);
			auto t3 = RBST::split(t2.first, RBST::size(t2.first) - 1);
			s = RBST::merge(RBST::merge(t1.first,RBST::merge(t3.second, t3.first)), t2.second);
		}else if(x==1){
			z++;
			auto t1 = RBST::split(s, y);
			auto t2 = RBST::split(t1.second, z - y);
			printf("%d\n",RBST::get_min(t2.first));
			s = RBST::merge(t1.first,RBST::merge(t2.first,t2.second));
		}else{
			auto t1 = RBST::split(s,y);
			auto t2 = RBST::split(t1.second, 1);
			*t2.first = RBST(z);
			s = RBST::merge(t1.first,RBST::merge(t2.first,t2.second));
		}
	}
}