AC的二分写法：

fo(l+1,i,r-1){
	ll l=L[i],r=R[i],re=0;
	while(l<=r){
		ll mid=l+r>>1;
		if(d[mid]+lazy[i]>=k) r=mid-1,re=R[i]-mid+1;
		else l=mid+1; 
	}
	ans+=re;
}

WA90的写法：

fo(l+1,i,r-1){
	ll l=L[i],r=R[i];
	while(l<r){
		ll mid=l+r>>1;
		if(d[mid]+lazy[i]>=k) r=mid;
		else l=mid+1; 
	}
	ans+=(R[i]-l+1);
}

两者有什么区别吗