//#pragma GCC optimize(3)

#include<bits/stdc++.h>
#define MST(a,b) memset(a,b,sizeof(a))
#define pb push_back
#define eb emplace_back
#define rep(i,a,b) for(int i = a ; i < b ; ++i)
#define per(i,a,b) for(int i = a ; i > b ; --i)
#define ALL(v) v.begin(),v.end()
#define ft first
#define sd second
using namespace std;
namespace fast_IO{
    const int maxbuff = 1<<17;
    char ibuff[maxbuff],obuff[maxbuff];
    inline char Getchar(){
        static char *p1=ibuff,*p2=ibuff;
        if(p1 == p2) {
            p1 = ibuff;
            p2 = ibuff+fread(ibuff,1,maxbuff,stdin);
            if(p1 == p2) return -1;
        }
        return *p1++;
    }

    int optr = 0;
    inline void Putchar(char c) {
        if(optr == maxbuff) {fwrite(obuff,1,optr,stdout);optr = 0;}
        obuff[optr++] = c;
    }

    inline void Flush() {
        fwrite(obuff,1,optr,stdout);
    }

    template<class T>
    inline int read(T &x) {
        x = 0;
        char c = Getchar();
        if(c == EOF) return -1;
        for( ; (c < '0' || c > '9') && c != EOF ; c = Getchar());
        if(c == EOF) return -1;
        for( ; c >= '0' && c <= '9' ; c = Getchar()) x = x*10+c-'0';
        return 0;
    }

    template<class T>
    inline void write(const T &x,int tag = 0) {
        if(!x) {
            if(!tag) Putchar(x+'0');
            return ;
        }
        write(x/10,1);
        Putchar(x%10+'0');
    }

    template<class T>
    inline void writeln(const T &x) {
        write(x);Putchar('\n');
    }

    template<class T>
    inline void writesp(const T &x) {
        write(x);Putchar(' ');
    }
}
template<class T> void show(T *x,int len,int s = 0) {for(int i = s ; i < s+len-1 ; ++i) cerr << x[i] << ' ';cerr << x[s+len-1] << endl;}
void debug() {cerr << endl;}
template <typename T, typename... Args> void debug(T x,Args... args) {cerr << x << ' ';debug(args...);}
typedef long long LL;
typedef unsigned long long ULL;
typedef pair<int,int> pii;
#include <ext/pb_ds/priority_queue.hpp>
using namespace __gnu_pbds;
typedef __gnu_pbds::priority_queue<pii,greater<>,pairing_heap_tag> heap;
typedef heap::point_iterator iter;

template<class T>
inline void cmin(T &A,const T &B) {A = (A<B?A:B);}
template<class T>
inline void cmax(T &A,const T &B) {A = (A>B?A:B);}

const int N = 3e5+19;
int _[N],tot,f[N];
vector<int> e[N];
pii line[N];
int n;

void solve() {
    cin >> n;
    int mx = 0;
    for(int i = 1 ; i <= n ; ++i) {
        int x,y;
        cin >> x >> y;
        line[i].first = x-y;
        line[i].second = x+y;
        _[++tot] = line[i].first;
        _[++tot] = line[i].second;
    }
    sort(_+1,_+tot+1);
    tot = unique(_+1,_+tot+1) - _;
    for(int i = 1 ; i <= n ; ++i) {
        if(line[i].first > 0) line[i].first = lower_bound(_+1,_+tot+1,line[i].first)-_;
        else line[i].first = 0;
        line[i].second = lower_bound(_+1,_+tot+1,line[i].second)-_;
        mx = max(mx,line[i].first);
        mx = max(mx,line[i].second);
        e[line[i].second].push_back(line[i].first);
    }
    for(int i = 1 ; i <= mx ; ++i) {
        f[i] = f[i-1];
        for(auto v : e[i])
            f[i] = max(f[i],f[v]+1);
    }
    cout << f[mx] << endl;

}

signed main() {
#ifdef LOCAL
    freopen("input","r",stdin);
    //freopen("output","w",stdout);
#endif
    srand((int)time(0));
    ios::sync_with_stdio(0);
    int T = 1;
    //cin >> T;
    while(T--) solve();
}

Measured memory_bytes: 13184