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

char*mmap();

#define rd_skip() while(*rp++>=48)
#define rd(v) long v=0;{long _c;while(_c=*rp++-48,_c>=0)v=v*10+_c;}
#define wt(v) {long _z=v;do*--wp=_z%10+48;while(_z/=10);}

int c[400000][2];

main(){
	long z=0;
	char*rp=mmap(0l,1l<<25,1,2,0,0ll);
	rd_skip();
	while(*rp){
		rd(a);
		rd(b);
		rd(t);
		long d=b-t+200000;
		z+=c[d][a^1];
		++c[d][a];
	}

	char wbuf[64],*wp=wbuf+sizeof wbuf;
	wt(z);
	write(1,wp,wbuf+sizeof wbuf-wp);
	_exit(0);
}