MCM

/*
    Task    : _example
    Author  : Phumipat C. [MAGCARI]
    Language: C++
    Created : 02 January 2023 [21:16]
*/
#include<bits/stdc++.h>
using namespace std;
struct A{
    int r,c,id;
};
A a[110];
int dp[110][110],cut[110][110];
int recur(int l,int r){
    if(l == r)      return 0;
    if(dp[l][r])    return dp[l][r];
    int now,mn = 1e9;
    for(int k=l;k<r;k++){
        now = recur(l,k) + recur(k+1,r) + (a[l].r * a[k].c * a[r].c);
        if(now < mn){
            mn = now;
            cut[l][r] = k;
        }
    }
    return dp[l][r] = mn;
}
void printOrder(int l,int r){
    if(l == r){
        cout << a[l].id;
        return ;
    }
    cout << '(';
    printOrder(l,cut[l][r]);
    cout << " x ";
    printOrder(cut[l][r]+1,r);
    cout << ')';
}
int main(){
    cin.tie(0)->sync_with_stdio(0);
    cin.exceptions(cin.failbit);
    int n;
    cin >> n;
    for(int i=1;i<=n;i++)
        cin >> a[i].r >> a[i].c,a[i].id = i;
    int ans = recur(1,n);
    cout << ans << '\n';
    printOrder(1,n);
    return 0;
}