#include<iostream>
#include<cstdio>
#include<algorithm>
#include<cstring>
using namespace std;
#define ll long long
const int maxn=1e2+5;
const int INF=0x3f3f3f3f;

int dp[105][105];
int pos[105][105];
char str[105];

int Find(int x,int y)
{
    if((str[x]==‘(‘ && str[y]==‘)‘) || (str[x]==‘[‘ && str[y]==‘]‘)) return 1;
    else return 0;
}

void print(int x,int y)
{
    if(x>y) return;
    if(x==y)
    {
        if(str[x]==‘[‘ || str[x]==‘]‘) printf("[]");
        else printf("()");
    }
    else
    {
        if(pos[x][y]>=0)
        {
            print(x,pos[x][y]);
            print(pos[x][y]+1,y);
        }
        else if(str[x]==‘(‘)
        {
            printf("(");
            print(x+1,y-1);
            printf(")");
        }
        else
        {
            printf("[");
            print(x+1,y-1);
            printf("]");
        }
    }
}

int main()
{
    //freopen("in.txt","r",stdin);
    scanf("%s",str+1);
    memset(pos,-1,sizeof(pos));
    memset(dp,0,sizeof(dp));
    int n=strlen(str+1);
    for(int i=1; i<=n; i++) dp[i][i]=1;
    for(int d=1; d<n; d++)
    {
        for(int i=1; i+d<=n; i++)
        {
            int j=i+d;
            dp[i][j]=INF;
            for(int k=i; k<j; k++)
            {
                if(dp[i][k]+dp[k+1][j]<dp[i][j])
                {
                    dp[i][j]=dp[i][k]+dp[k+1][j];
                    pos[i][j]=k;
                }
            }
            if( Find(i,j) && dp[i+1][j-1]<dp[i][j] )
            {
                dp[i][j]=dp[i+1][j-1];
                pos[i][j]=-1;
            }
        }
    }
    print(1,n);
    puts("");
    return 0;
}