标签：ble blank lse 注意 core 最大数 def const ace
考察:二分
思路:
首先这道题不是让我们求坐标,而是求具体的值.观察式子,当j不变时,i增大,值增大.分数满足单调性,j不变时,i也满足单调性.二分分数,枚举每一列有多少个满足分数＜小于当前score,根据总数再继续二分score.在枚举每一列时,i也满足单调性,所以也用二分枚举i.
注意:二分get(mid,j)<score时,二分结束的值是满足此性质的最大数....不要搞成第一个==score的数....
1 #include <iostream> 2 #include <cstring> 3 #include <cstdio> 4 using namespace std; 5 typedef long long LL; 6 const LL Maxn = 7500000000LL,Minv = -2499859999LL; 7 int n; 8 LL m; 9 LL get(int i,int j) 10 { 11 LL res = (LL)i*i +100000ll*i + (LL)j*j-100000ll*j+(LL)i*j; 12 return res; 13 } 14 int check(int j,LL score) 15 { 16 int l = 0,r = n; 17 while(l<r) 18 { 19 int mid = l+r+1>>1; 20 if(get(mid,j)<score) l = mid; 21 else r = mid-1; 22 } 23 return r; 24 } 25 int main() 26 { 27 int T; 28 scanf("%d",&T); 29 while(T--) 30 { 31 scanf("%d%lld",&n,&m); 32 LL l = Minv,r = Maxn; 33 while(l<r) 34 { 35 LL mid = l+r+1>>1,res = 0; 36 for(int i=1;i<=n;i++) 37 res+=check(i,mid); 38 if(res<m) l = mid; 39 else r = mid-1; 40 } 41 printf("%lld\n",r); 42 } 43 return 0; 44 }
标签：ble blank lse 注意 core 最大数 def const ace
原文地址：https://www.cnblogs.com/newblg/p/14489215.html
