#pragma GCC optimize("Ofast")
#pragma GCC target("avx2")

#define _GNU_SOURCE 1
#include <sys/mman.h>

#define RD(v) int v=0;{int c;while(c=*rp++-48,c>=0)v=v*10+c;}
#define RDN(v) int v=0;{int neg=*rp==45?++rp,1:0;RD(_t);v=neg?-_t:_t;}

int h[300001];

main(){
	char*rp=mmap(0,1600l<<10,PROT_READ,MAP_PRIVATE|MAP_POPULATE,0,0ll);
	while(*rp++!=10);
	do{
		RDN(x); x+=100000;
		RD(r);
		++h[x-r<0?0:x-r];
		--h[x+r];
	}while(*rp);

	int y=0,z=0;
	for(int i=0;i<200000;++i){
		y+=h[i];
		z=z>=y?z:y;
	}

	char wbuf[16],*wp=wbuf+sizeof wbuf;
	while(*--wp=z%10+48,z/=10);
	write(1,wp,(wbuf+sizeof wbuf)-wp);
	_exit(0);
}