Educational Codeforces Round 20 B. Distances to Zero

B. Distances to Zero
time limit per test
2 seconds
memory limit per test
256 megabytes
input
standard input
output
standard output

You are given the array of integer numbers a0, a1, ..., an - 1. For each element find the distance to the nearest zero (to the element which equals to zero). There is at least one zero element in the given array.

Input

The first line contains integer n (1 ≤ n ≤ 2·105) — length of the array a. The second line contains integer elements of the array separated by single spaces ( - 109 ≤ ai ≤ 109).

Output

Print the sequence d0, d1, ..., dn - 1, where di is the difference of indices between i and nearest j such that aj = 0. It is possible that i = j.

Examples
input
9
2 1 0 3 0 0 3 2 4
output
2 1 0 1 0 0 1 2 3 
input
5
0 1 2 3 4
output
0 1 2 3 4 
input
7
5 6 0 1 -2 3 4
output
2 1 0 1 2 3 4 

 这道题真没什么难的啊,但是昨晚自己竟然没做,一直在想A和C,不过昨晚也就做了半个多小时,甚至还不到?这道题的意思就是找离它最近的0的距离,那就是只用找它两边的0就好了,我写的复杂程度应该是0(k*n),我把那个min函数省了,这样可以有效的节省时间啊,毕竟被这个坑过,就是二分一下,因为我的区间是左闭又开,所以中间值要在和上加1,这个东西调的有点久,其实是变量自己莫名写错,找不到错误。代码很简单,看一下应该都懂。

#include <stdio.h>
#include <algorithm>
using namespace std;
int a[200005];
int main()
{int n;
scanf("%d",&n);
int f=1,c=0;
int p;
for(int i=1;i<=n;i++){
    scanf("%d",&p);
    if(!p)
    a[f++]=i;
}
int r=a[1],l;
for(int i=1;i<r;i++){
if(c)printf(" ");c=1;
printf("%d",r-i);
}
for(int i=1;i<f-1;i++){
l=a[i],r=a[i+1];
int s=(l+r+1)/2;
for(int j=l;j<s;j++){
if(c)printf(" ");c=1;
printf("%d",j-l);
}
for(int j=s;j<r;j++){
if(c)printf(" ");c=1;
printf("%d",r-j);
}}
l=a[f-1];
for(int i=l;i<=n;i++){
if(c)printf(" ");c=1;
printf("%d",i-l);}
    return 0;
}
View Code

 

posted @ 2017-04-29 12:36  暴力都不会的蒟蒻  阅读(328)  评论(0编辑  收藏  举报