#include <cstdio>

#include <cstring>

#include <cmath>

#include <string>

#include <iostream>

#include <algorithm>

#include <queue>

#include <set>

#include <map>

using namespace std;

typedef long long ll;

#define rep(i, n) for(int i=0; i<(n); ++i)

#define for1(i,a,n) for(int i=(a);i<=(n);++i)

#define for2(i,a,n) for(int i=(a);i<(n);++i)

#define for3(i,a,n) for(int i=(a);i>=(n);--i)

#define for4(i,a,n) for(int i=(a);i>(n);--i)

#define CC(i,a) memset(i,a,sizeof(i))

#define read(a) a=getint()

#define print(a) printf("%d", a)

#define dbg(x) cout << (#x) << " = " << (x) << endl

#define error(x) (!(x)?puts("error"):0)

#define rdm(x, i) for(int i=ihead[x]; i; i=e[i].next)

inline const int getint() { int r=0, k=1; char c=getchar(); for(; c<'0'||c>'9'; c=getchar()) if(c=='-') k=-1; for(; c>='0'&&c<='9'; c=getchar()) r=r*10+c-'0'; return k*r; }

const int N=200005;

struct node *null;

struct node {

	node *c[2], *f;

	int s, k, sum;

	bool rev;

	node(int _k=0) { c[0]=c[1]=f=null; s=1; k=sum=_k; rev=0; }

	void pushup() { s=1+c[0]->s+c[1]->s; sum=k+c[0]->sum+c[1]->sum; }

	void setc(node *x, bool d) { c[d]=x; x->f=this; }

	bool d() { return f->c[1]==this; }

	void upd() {

		if(this==null) return;

		rev=!rev;

		swap(c[0], c[1]);

	}

	void pushdown() {

		if(rev) {

			rev=0;

			c[0]->upd();

			c[1]->upd();

		}

	}

}*root;

void rot(node *x) {

	node *f=x->f;

	f->pushdown(); x->pushdown(); bool d=x->d();

	f->f->setc(x, f->d());

	f->setc(x->c[!d], d);

	x->setc(f, !d);

	f->pushup();

	if(f==root) root=x;

}

void splay(node *x, node *f=null) {

	x->pushdown();

	while(x->f!=f) {

		if(x->f->f==f) rot(x);

		else x->d()==x->f->d()?(rot(x->f), rot(x)):(rot(x), rot(x));

	}

	x->pushup();

}

void Pr(node *x) {

	if(x==null) return;

	Pr(x->c[0]);

	printf("%c", x->k?'(':')');

	Pr(x->c[1]);

}

void P(node *x=root) {

	Pr(x); puts("");

}

void init() { null=new node; null->s=0; null->c[0]=null->c[1]=null->f=null; root=null; }

void build(char *s, int l, int r, node *&x) {

	if(l>r) return;

	int mid=(l+r)>>1;

	x=new node(s[mid]=='(');

	if(l==r) return;

	build(s, l, mid-1, x->c[0]);

	build(s, mid+1, r, x->c[1]);

	if(l<=mid-1) x->c[0]->f=x;

	if(mid+1<=r) x->c[1]->f=x;

	x->pushup();

}

void build(char *s) {

	int len=strlen(s);

	node *x=null;

	root=new node();

	x=new node();

	root->setc(x, 1);

	x=new node();

	build(s-1, 1, len, x);

	root->c[1]->setc(x, 0);

	root->c[1]->pushup();

	root->pushup();

}

node* find(node *x) {

	if(x==null) return null;

	x->pushdown();

	if(x->c[0]->sum==0 && x->k) return x; //这里啊啊啊

	if(x->c[0]->sum) return find(x->c[0]);

	return find(x->c[1]);

}

node* sel(node *x, int k) {

	if(x==null) return null;

	x->pushdown();

	int s=x->c[0]->s;

	if(s==k) return x;

	if(s<k) return sel(x->c[1], k-s-1);

	else return sel(x->c[0], k);

}

node* getrange(int l, int r) {

	splay(sel(root, l-1));

	splay(sel(root, r+1), root);

	return root->c[1]->c[0];

}

int getpos(int l, int r) {

	node *x=getrange(l, r);

	x=find(x); //dbg(x->k);

	splay(x);

	return x->c[0]->s;

}

void fix(int l, int r) {

	node *x=getrange(l, r); //P(x);

	x->upd();

	root->c[1]->pushup();

	root->pushup();

}

int getinf(int l) {

	node *r=getrange(l, l);

	return r->k;

}

char s[N];

int ans;

int x[N], y[N], n, len;

// int ifind(int now) {

// 	int ret=now;

// 	while(ret<=len) if(s[ret]=='(') return ret; else ++ret;

// 	return 0;

// }

// void fix(int l, int r) {

// 	while(l<r) swap(s[l], s[r]), ++l, --r;

// }

int main() {

	scanf("%s", s+1);

	init();

	len=strlen(s+1);

	//dbg(s+1);

	n=len>>1;

	build(s+1);

	//dbg(getpos(2, len));

	//fix(1, getpos(2, len));

	//node *xx=sel(root, 1); dbg(xx->s); P();

	for1(i, 1, n) {

		//printf("%c\n", getinf(i)?'(':')');

		if(getinf(i)!=1) {

			++ans;

			int pos=getpos(i+1, len);

			if(!pos) { puts("error"); return 0; }

			x[ans]=i;

			y[ans]=pos;

			fix(i, pos);

			//dbg(s+1);

		}

		//P();

	}

	printf("%d\n", ans);

	for1(i, 1, ans) {

		printf("%d %d\n", x[i], y[i]);

	}

	return 0;

}