#include<bits/stdc++.h>
#define int long long
using namespace std;
const int N=2e5+10;
struct node{
    int s;
    char c;
}a[N];
int n;
signed main()
{
    cin>>n;
    for(int i=1;i<=n;i++){
        cin>>a[i].s>>a[i].c;
    }
    int l=1,r=n,t1=0,t2=0;
    int ans=0;
    while(true){
        int x,y;
        x=a[l].s-t1;
        y=a[r].s-t2;
        int minv=min(x,y);
        if(l>=r){
            break;
        }
        if(a[l].c!=a[r].c){
            ans+=minv;
        }
        if(x<y){
            l++,t1=0;
            t2+=minv;
        }
        else if(x>y){
            r--,t2=0;
            t1+=minv;
        }
        else{
            l++,r--;
            t1=t2=0;
        }
    }
    cout<<ans;
    return 0;
}

#include<bits/stdc++.h>
using namespace std;
#define ll long long
const int N = 2e5+5;
struct node {
	ll a;
	char c;
	//a琛ㄧず涓暟,c琛ㄧず瀛楃
} s[N];
ll n;
int main() {
//	freopen("string.in", "r", stdin);
//	freopen("string.out", "w", stdout);
	cin >> n;
	for (int i = 1; i <= n; i++) {
		cin >> s[i].a >> s[i].c;
	}
	ll i = 1, j = n;
	ll t1 = 0, t2 = 0;
	ll ans = 0;
	while (true) {
		if (i >= j) break;
		ll p1, p2;
		p1 = s[i].a - t1, p2 = s[j].a - t2;
		ll minv = min(p1, p2);
		bool b = (s[i].c == s[j].c);
		if (!b) {
			ans += minv;
		}
		if (p1 < p2) {
			i++;
			t1 = 0;
			t2 += minv;
		} else if (p1 > p2) {
			j--;
			t2 = 0;
			t1 += minv;
		} else {
			i++, j--;
			t1 = 0, t2 = 0;
		}
	}
	cout << ans;
	return 0;
}

#include<bits/stdc++.h>
using namespace std;
#define ll long long
const int N = 2e5+5;
struct node {
	ll a;
	char c;
	//a琛ㄧず涓暟,c琛ㄧず瀛楃
} s[N];
ll n;
int main() {
//	freopen("string.in", "r", stdin);
//	freopen("string.out", "w", stdout);
	cin >> n;
	for (int i = 1; i <= n; i++) {
		cin >> s[i].a >> s[i].c;
	}
	ll i = 1, j = n;
	ll t1 = 0, t2 = 0;
	ll ans = 0;
	while (true) {
		if (i == j) break;
		ll p1, p2;
		p1 = s[i].a - t1, p2 = s[j].a - t2;
		ll minv = min(p1, p2);
		bool b = (s[i].c == s[j].c);
		if (!b) {
			ans += minv;
		}
		if (p1 < p2) {
			i++;
			t1 = 0;
			t2 += minv;
		} else if (p1 > p2) {
			j--;
			t2 = 0;
			t2 += minv;
		} else {
			i++, j++;
			t1 = 0, t2 = 0;
		}
	}
	cout << ans;
	return 0;
}