It’s universally acknowledged that there’re innumerable trees in the campus of HUST.
Now you're going to walk through a large forest. There is a path consisting of N stones winding its way to the other side of the forest. Between every two stones there is a distance. Let d
i indicates the distance between the stone i and i+1.Initially you stand at the first stone, and your target is the N-th stone. You must stand in a stone all the time, and you can stride over arbitrary number of stones in one step. If you stepped from the stone i to the stone j, you stride a span of (d
i+d
i+1+...+d
j-1). But there is a limitation. You're so tired that you want to walk through the forest in no more than K steps. And to walk more comfortably, you have to minimize the distance of largest step.
输入描述:
The first line contains two integer N and K
as described above.
Then the next line N-1 positive integer followed, indicating the distance between two adjacent stone
.
输出描述:
An integer, the minimum distance of the largest step.
示例1
输入
6 3 1 3 2 2 5
输出
5
题意: 输入 n,k 下面为 n-1个数,为n个石头相邻的距离, 在不超过 他可以跳任意距离,求 在跳的不超k下的,所跳的最大距离的最小值;
比赛时提交错了,比赛后 把错误的代码又提交了一次 过了,无语。。。
代码:
#include<stdio.h> #include<string.h> #include<algorithm> using namespace std; #define Max 100010 #define ll long long ll a[Max]; ll n,m; int main() { ll i,j; while(~scanf("%lld%lld",&n,&m)) { ll Ma = -1; ll sum = 0; for(i = 0;i<n-1;i++) { scanf("%lld",&a[i]); Ma = max(Ma,a[i]); sum += a[i]; } ll flag = 1; ll l = Ma,r = sum; while(l<=r) { ll mid = (l+r)/2; sum = 0; ll num = 0; for(i = 0;i<n;i++) { if(sum+a[i]>mid) { num ++; sum = 0; sum +=a[i]; } else sum += a[i]; } num++; if(num<=m) { flag = mid; r = mid - 1; } else { l = mid + 1; } } printf("%lld\n",flag); } return 0; }