There are n cities numbered from 1 to n, and city i has beauty a_i.

A salesman wants to start at city 1, visit every city exactly once, and return to city 1.

For all i≠ j, a flight from city i to city j costs max(c_i,a_j-a_i) dollars, where c_i is the price floor enforced by city i. Note that there is no absolute value. Find the minimum total cost for the salesman to complete his trip.

Input

The first line contains a single integer n (2≤ n≤ 10^5) — the number of cities.

The i-th of the next n lines contains two integers a_i, c_i (0≤ a_i,c_i≤ 10^9) — the beauty and price floor of the i-th city.

Output

Output a single integer — the minimum total cost.

Examples

Input


3
1 9
2 1
4 1


Output


11


Input


6
4 2
8 4
3 0
2 3
7 1
0 1


Output


13

Note

In the first test case, we can travel in order 1→ 3→ 2→ 1. 

  * The flight 1→ 3 costs max(c_1,a_3-a_1)=max(9,4-1)=9. 
  * The flight 3→ 2 costs max(c_3, a_2-a_3)=max(1,2-4)=1. 
  * The flight 2→ 1 costs max(c_2,a_1-a_2)=max(1,1-2)=1. 



The total cost is 11, and we cannot do better.
// --------------------------------------------------<TEMPLATE>--------------------------------------------------
// --------------------<optimizations>--------------------
/*
#pragma GCC optimize("Ofast,unroll-loops")
#pragma GCC target("avx,avx2,fma")
*/ 
// -------------------</optimizations>--------------------
 
// ---------------<Headers and namespaces>----------------
#include <bits/stdc++.h>
using namespace std;
 
/*
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
*/
 
// ---------------</Headers and namespaces>---------------
 
// -----------------<Defines and typedefs>----------------
// typedef tree<int,null_type,less<int>,rb_tree_tag, 
// tree_order_statistics_node_update> indexed_set; // use less_equal for multiset
// order_of_key (val): returns the no. of values less than val
// find_by_order (k): returns the iterator to kth largest element.(0-based)
 
typedef long double LD;
typedef long long ll;
#define int ll
#define pb push_back
#define mp make_pair
#define REP(i,n) for (int i = 0; i < n; i++)
#define FOR(i,a,b) for (int i = a; i < b; i++)
#define REPD(i,n) for (int i = n-1; i >= 0; i--)
#define FORD(i,a,b) for (int i = a; i >= b; i--)
#define remax(a,b) a = max(a,b)
#define remin(a,b) a = min(a,b)
#define all(v) v.begin(),v.end()
typedef map<int,int> mii;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int,int> pii;
typedef vector<pii> vpii;
#define F first
#define S second
#define PQ(type) priority_queue<type>
#define PQD(type) priority_queue<type,vector<type>,greater<type> >
#define WL(t) while(t --)
#define SZ(x) ((int)(x).size())
#define runtime() ((double)clock() / CLOCKS_PER_SEC)
#define inrange(i,a,b) ((i>=min(a,b)) && (i<=max(a,b)))
 
/*
// -----<SCANF>-----
#define sfi(x) scanf("%d",&x);
#define sfi2(x,y) scanf("%d%d",&x,&y);
#define sfi3(x,y,z) scanf("%d%d%d",&x,&y,&z);
 
#define sfl(x) scanf("%lld",&x);
#define sfl2(x,y) scanf("%lld%lld",&x,&y);
#define sfl3(x,y,z) scanf("%lld%lld%lld",&x,&y,&z);
#define sfl4(x,y,z,x1) scanf("%lld%lld%lld%lld",&x,&y,&z,&x1);
#define sfl5(x,y,z,x1,y1) scanf("%lld%lld%lld%lld%lld",&x,&y,&z,&x1,&y1);
#define sfl6(x,y,z,x1,y1,z1) scanf("%lld%lld%lld%lld%lld%lld",&x,&y,&z,&x1,&y1,&z1);
 
#define sfs(x) scanf("%s",x);
#define sfs2(x,y) scanf("%s%s",x,y);
#define sfs3(x,y,z) scanf("%s%s%s",x,y,z);
// ----</SCANF>-----
 
// ----<PRINTF>-----
#define pfi(x) printf("%d\n",x);
#define pfi2(x,y) printf("%d %d\n",x,y);
#define pfi3(x,y,z) printf("%d %d %d\n",x,y,z);
 
#define pfl(x) printf("%lld\n",x);
#define pfl2(x,y) printf("%lld %lld\n",x,y);
#define pfl3(x,y,z) printf("%lld %lld %lld\n",x,y,z);
 
#define pfs(x) printf("%s\n",x);
#define pfs2(x,y) printf("%s %s\n",x,y);
#define pfs3(x,y,z) printf("%s %s %s\n",x,y,z);
 
#define pwe(x) printf("%lld ",x); // print without end
// ----</PRINTF>----
*/
#define FLSH fflush(stdout)
#define fileIO(name) \
    freopen(name".in", "r", stdin); \
    freopen(name".out", "w", stdout);
#define PRECISION(x) cout << fixed << setprecision(x); 
#define FAST_IO ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
 
// ----------------</Defines and typedefs>----------------
 
// -------------------<Debugging stuff>-------------------
#ifdef TRACE
#define trace(...) __f(#__VA_ARGS__, __VA_ARGS__)
template <typename Arg1>
void __f(const char* name, Arg1&& arg1){
    cout << name << " : " << arg1 << std::endl;
}
template <typename Arg1, typename... Args>
void __f(const char* names, Arg1&& arg1, Args&&... args){
    const char* comma = strchr(names + 1, ',');cout.write(names, comma - names) << " : " << arg1<<" | ";__f(comma+1, args...);
}
#else
#define trace(...)
#endif
 
// ------------------</Debugging stuff>-------------------
 
// ------------------------<Consts>-----------------------
const int MAXN = 200005;
const int SQRTN = 1003;
const int LOGN = 22;
const double PI=acos(-1);
 
#ifdef int
const int INF=1e16;
#else
const int INF=1e9;
#endif
 
const int MOD = 1000000007;
const int FMOD = 998244353;
const double eps = 1e-9;
// -----------------------</Consts>-----------------------
/*
// -------------------------<RNG>-------------------------
mt19937 RNG(chrono::steady_clock::now().time_since_epoch().count()); 
#define SHUF(v) shuffle(all(v), RNG);
// Use mt19937_64 for 64 bit random numbers.
 
// ------------------------</RNG>-------------------------
 
// ----------------------<MATH>---------------------------
template<typename T> T gcd(T a, T b){return(b?__gcd(a,b):a);}
template<typename T> T lcm(T a, T b){return(a*(b/gcd(a,b)));}
int add(int a, int b, int c = MOD){int res=a+b;return(res>=c?res-c:res);}
int mod_neg(int a, int b, int c = MOD){int res;if(abs(a-b)<c)res=a-b;else res=(a-b)%c;return(res<0?res+c:res);}
int mul(int a, int b, int c = MOD){ll res=(ll)a*b;return(res>=c?res%c:res);}
int muln(int a, int b, int c = MOD){ll res=(ll)a*b;return ((res%c)+c)%c;}
ll mulmod(ll a,ll b, ll m = MOD){ll q = (ll)(((LD)a*(LD)b)/(LD)m);ll r=a*b-q*m;if(r>m)r%=m;if(r<0)r+=m;return r;}
template<typename T>T expo(T e, T n){T x=1,p=e;while(n){if(n&1)x=x*p;p=p*p;n>>=1;}return x;}
template<typename T>T power(T e, T n, T m = MOD){T x=1,p=e;while(n){if(n&1)x=mul(x,p,m);p=mul(p,p,m);n>>=1;}return x;}
template<typename T>T extended_euclid(T a, T b, T &x, T &y){T xx=0,yy=1;y=0;x=1;while(b){T q=a/b,t=b;b=a%b;a=t;\
t=xx;xx=x-q*xx;x=t;t=yy;yy=y-q*yy;y=t;}return a;}
template<typename T>T mod_inverse(T a, T n = MOD){T x,y,z=0;T d=extended_euclid(a,n,x,y);return(d>1?-1:mod_neg(x,z,n));}
 
const int FACSZ = 1; // Make sure to change this
 
int fact[FACSZ],ifact[FACSZ];
 
void precom(int c = MOD){
    fact[0] = 1;
    FOR(i,1,FACSZ) fact[i] = mul(fact[i-1],i,c);
    ifact[FACSZ-1] = mod_inverse(fact[FACSZ-1],c);
    REPD(i,FACSZ-1){
        ifact[i] = mul(i+1,ifact[i+1],c);
    }
}
 
int ncr(int n,int r,int c = MOD){
    return mul(mul(ifact[r],ifact[n-r],c),fact[n],c);
} 
*/
// ----------------------</MATH>--------------------------
// --------------------------------------------------</TEMPLATE>--------------------------------------------------
 
void solvethetestcase();
 
signed main(){
    // comment when using scanf,printf
    FAST_IO
    int t = 1;
    // (UNCOMMENT FOR MULTIPLE TEST CASES)
    // cin >> t;
    FOR(testcase,1,t+1){
        // (UNCOMMENT FOR CODEJAM)
        // printf("Case #%lld: ",testcase); 
        solvethetestcase();
    }
}   
 
int n;
pii a[MAXN];
 
void solvethetestcase(){
    cin >> n;
    int ans = 0,extra = 0;
    REP(i,n){
        cin >> a[i].F >> a[i].S;
    }
    sort(a,a+n);
    REP(i,n-1){
        int op1 = a[i].S;
        int op2 = a[i+1].F-a[i].F-extra;
        ans += max(op1,op2);
        extra = max(0LL,op1-op2-a[i+1].S);
    }
    cout << ans+a[n-1].S << endl;
}