#include <bits/stdc++.h>
#define N 100009
#define ll long long
#define lson s[x].ch[0]
#define rson s[x].ch[1]
#define setIO(s) freopen(s".in","r",stdin)
using namespace std;
char str[N<<1];
int n,tot,root,A[N<<1],sta[N<<1];
struct node { int ch[2],rev,f,w,pos,si;
}s[N<<1];
int get(int x) { return s[s[x].f].ch[1]==x; }
void mark(int x)
{swap(lson,rson),s[x].rev^=1;
}
void pushup(int x)
{int l=lson,r=rson;   s[x].si=s[l].si+s[r].si+1;                                          if(s[x].w==1) s[x].pos=x;   else s[x].pos=0;              if(s[l].pos)  s[x].pos=s[l].pos;             if(s[r].pos)  s[x].pos=s[r].pos;
}
void pushdown(int x)
{      if(s[x].rev) {if(lson) mark(lson); if(rson) mark(rson);  s[x].rev=0;  }
}
void rotate(int x)
{ int old=s[x].f,fold=s[old].f,which=get(x);  s[old].ch[which]=s[x].ch[which^1];  if(s[old].ch[which]) s[s[old].ch[which]].f=old;  s[x].ch[which^1]=old,s[old].f=x,s[x].f=fold;   if(fold) s[fold].ch[s[fold].ch[1]==old]=x;   pushup(old),pushup(x);
}
void splay(int x,int &tar)
{int fa,u=x,v=0; for(sta[++v]=u;u!=tar;u=s[u].f) sta[++v]=s[u].f;              for(;v;--v) pushdown(sta[v]);   for(u=s[u].f;(fa=s[x].f)!=u;rotate(x))  if(s[fa].f!=u) rotate(get(fa)==get(x)?fa:x);   tar=x;
}
int find(int x,int kth)
{                         pushdown(x);   if(s[lson].si+1==kth) return x;   else{if(s[lson].si>=kth) return find(lson,kth);   else return find(rson,kth-s[lson].si-1);  }
}
int build(int l,int r,int ff)
{     int mid=(l+r)>>1;  int cur=++tot;    s[cur].f=ff;   s[cur].w=A[mid];       if(mid>l) s[cur].ch[0]=build(l,mid-1,cur);   if(r>mid) s[cur].ch[1]=build(mid+1,r,cur);    pushup(cur);   return cur;
}
int cnt;
int tl[N],tr[N];
int main()
{ // setIO("input");scanf("%s",str+1),n=strlen(str+1);   for(int i=1;i<=n;++i) A[i]=(str[i]=='('?1:-1);root=build(0,n+1,0);                 for(int i=1;i<=n/2;++i) {        int CUR;        splay(CUR=find(root,i+1),root);                                  if(s[root].w==1) continue;     else{                                  int PRE=find(root,i);            splay(PRE,root);     int z=s[s[PRE].ch[1]].pos;      splay(z,root);      int k=s[s[z].ch[0]].si+1;   splay(PRE,root);       splay(find(root,k+1),s[PRE].ch[1]);    int tmp=s[s[PRE].ch[1]].ch[0];    mark(tmp);  ++cnt;   tl[cnt]=i,tr[cnt]=k-1;  }}printf("%d\n",cnt);        for(int i=1;i<=cnt;++i) printf("%d %d\n",tl[i],tr[i]);      return 0;
}