[杂题 贪心] BZOJ4723: [POI2017]Flappy Bird

#include<cstdio>
#include<algorithm>
using namespace std;
const int maxn=500005;
int n,x[maxn],a[maxn],b[maxn],now_L,now_R;
int main(){
scanf("%d%*d",&n);
for(int i=1;i<=n;i++) scanf("%d%d%d",&x[i],&a[i],&b[i]), a[i]++, b[i]--;
for(int i=1;i<=n;i++){
int dis=x[i]-x[i-1];
now_L=max(now_L-dis,a[i]);
now_R=min(now_R+dis,b[i]);
if((now_L+x[i])&1) now_L++;
if((now_R+x[i])&1) now_R--;
if(now_L>now_R) return printf("NIE"),0;
}
printf("%d\n",(now_L+x
)>>1);
return 0;
}