48 lines
820 B
C++
48 lines
820 B
C++
#include<iostream>
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#include <algorithm>
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using namespace std;
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int n;
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bool ce[100001]={0};
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struct link{
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int x,y;
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}a[100001];
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bool pan(link yi,link er){
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return yi.x<er.x;
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}
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int main(){
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cin>>n;
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for(int i=0;i<n;i++){
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cin>>a[i].x>>a[i].y;
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}
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sort(a,a+n,pan);
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/*
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for (int i = 0; i <n; i++) {
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cout<<a[i].x<<" "<<a[i].y <<endl;
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}*/
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int now=0,ans=n;
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for(int i=1;i<n;i++){
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if(a[now].y+a[now].x-a[i].x>=a[i].y){
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ce[i]=1;
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//cout<<ans<<" "<<a[i].x<<" "<<a[i].y <<endl;
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}else{
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now=i;
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}
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}
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now=n-1;
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if(ce[now]==1){
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ans--;
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}
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for(int i=n-2;i>=0;i--){
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if(a[now].y-(a[now].x-a[i].x)>=a[i].y){
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ce[i]=1;
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//cout<<ans<<" "<<a[i].x<<" "<<a[i].y <<endl;
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}else{
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now=i;
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}
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if(ce[i]==1){
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ans--;
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}
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}
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cout<<ans;
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}
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