CF527D Clique Problem(贪心)

考场上想的线性(DP)，思路没错但还是(WA)穿。。。多看两眼就知道是最大线段不重复覆盖问题
右端点第一关键字排序

#include <iostream>
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <algorithm>
#include <cmath>
#define R(a,b,c) for(register int a = (b); a <= (c); ++a)
#define nR(a,b,c) for(register int a = (b); a >= (c); --a)
#define Fill(a,b) memset(a, b, sizeof(a))
#define Swap(a,b) ((a) ^= (b) ^= (a) ^= (b))
#define QWQ
#ifdef QWQ
#define D_e_Line printf("
---------------
")
#define D_e(x) cout << (#x) << " : " << x << "
"
#define Pause() system("pause")
#define FileOpen() freopen("in.txt", "r", stdin)
#define FileSave() freopen("out.txt", "w", stdout)
#define TIME() fprintf(stderr, "
TIME : %.3lfms
", clock() * 1000.0 / CLOCKS_PER_SEC)
#else
#define D_e_Line ;
#define D_e(x) ;
#define Pause() ;
#define FileOpen() ;
#define FileSave() ;
#define TIME() ;
#endif
struct ios {
	template<typename ATP> inline ios& operator >> (ATP &x) {
		x = 0; int f = 1; char c;
		for(c = getchar(); c < '0' || c > '9'; c = getchar()) if(c == '-') f = -1;
		while(c >= '0' && c <='9') x = x * 10 + (c ^ '0'), c = getchar();
		x *= f;
		return *this;
	}
}io;
using namespace std;
template<typename ATP> inline ATP Max(ATP a, ATP b) {
	return a > b ? a : b;
}
template<typename ATP> inline ATP Min(ATP a, ATP b) {
	return a < b ? a : b;
}
template<typename ATP> inline ATP Abs(ATP a) {
	return a < 0 ? -a : a;
}

#define int long long
struct nod {
	int l, r;
	bool operator < (const nod &com) const {
		return r != com.r ? r < com.r : l < com.l;
	}
} a[2000007];
#include <climits>
#undef int
int main() {
#define int long long
	int n;
	io >> n;
	R(i,1,n){
		int x, w;
		io >> x >> w;
		a[i] = (nod){ x - w, x + w};
	}
	
	sort(a + 1, a + n + 1);
	int r = -LLONG_MAX;
	int ans = 0;
	R(i,1,n){
		if(a[i].l < r) continue;
		++ans;
		r = a[i].r;
	}
	printf("%lld", ans);
	
	return 0;
}