#include <bits/stdc++.h> #define ii pair<int, int> #define fi first #define se second #define inf 0x3f3f3f3f3f3f3f3f using namespace std; using ll = long long; const ll mod=1e9+7; const int nx=1e7+5; int n, ans=0, cur=-1, x, y; stack<ii> st; ii p; bool ok; static const int BUF_SIZE = 1 << 20; char buf[BUF_SIZE]; int bi = BUF_SIZE, bn = BUF_SIZE; inline char readCharFast() { if (bi >= bn) { bn = fread(buf, 1, BUF_SIZE, stdin); bi = 0; if (bn == 0) return 0; } return buf[bi++]; } inline bool fastReadInt(int &x) { char c; do c = readCharFast(); while (c <= ' ' && c != 0); if (!c) return false; int sign = 1; if (c == '-') { sign = -1; c = readCharFast(); } int val = c - '0'; while (1) { c = readCharFast(); if (c < '0' || c > '9') break; val = val * 10 + (c - '0'); } x = val * sign; return true; } int main() { ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); cin>>n; while(n--) { fastReadInt(x); fastReadInt(y); ok=1; while(st.size()) { p=st.top(); if(x-p.fi<=p.se-y) { ok=0; break; } if(x-p.fi<=y-p.se) st.pop(); else break; } if(ok) st.push({x, y}); } cout<<st.size(); }