二分

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 2e5+5;
struct node{ll st,ed,d;}a[N];
int n;
ll S(ll x)//计算前缀和
{
	ll res= 0;
	for(int i=1;i<=n;i++)if(a[i].st<=x)
        res+= (min(x,a[i].ed) - a[i].st) / a[i].d + 1;
	return res;
}
bool check(ll x,ll y)//判断当前区间是否有奇数个防具
{
	return ( S(y) - S(x-1) ) % 2 == 1;
}
int main()
{
	int T;scanf("%d",&T);
	while(T--)
	{
		scanf("%d",&n);
		ll L = 1ll<<60,R = 0;
		for(int i=1;i<=n;i++)
		{
			scanf("%lld%lld%lld",&a[i].st,&a[i].ed,&a[i].d);
			L = min(L,a[i].st),R = max(R,a[i].ed);
		}
		if(!check(L,R))
		{
			printf("There's no weakness.\n");
			continue;
		}
		ll l = L,r = R,p = 0;
		while(l <= r)
		{
			ll mid=(l+r)>>1;
			if(check(l,mid)) r=mid-1,p=mid;
			else             l=mid+1;
		}
		printf("%lld %lld\n",p , S(p)-S(p-1) );
	}
	return 0;
}

位运算

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N=2e5+5;
struct node{ll st,ed,d;}a[N];

int main()
{
	int T;scanf("%d",&T);
	while(T--)
    {
		int n;scanf("%d",&n);
		ll p=0;
		for(int i=1;i<=n;i++)
        {
			ll st,ed,d;scanf("%lld%lld%lld",&st,&ed,&d);
			a[i]={st,ed,d};
			for(ll k=st;k<=ed;k+=d) p^=(k+1); //排除k=0的特殊情况
		}
		if(p==0)
        {
		    printf("There's no weakness.\n");
		    return 0;
		}

		p--;
		ll num=0;
		for(int i=1;i<=n;i++) if(a[i].st<=p && p<=a[i].ed)
            num+= ( (p-a[i].st)%a[i].d ==0 ) ;

		printf("%lld %lld\n",p,num);
	}
    return 0;
}