【Codeforces 803 B. Distances to Zero】

B. Distances to Zero
time limit per test2 seconds
memory limit per test256 megabytes
inputstandard input
outputstandard 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

1）记录下每个零的位置
2）求与该位置最近的零的距离

AC代码：

#include<cstdio>#include<algorithm>using namespace std;const int K = 2e5 + 10;int a[K],b[K];int main(){    int n,nl = 0,c;    scanf("%d",&n);    for(int i = 1; i <= n; i++){        scanf("%d",&a[i]);        if(!a[i])            b[++nl] = i;    }    b[0] = -1e9;    int pl = 1;    for(int i = 1; i <= n; i++){        if(!a[i] && pl < nl)            pl++;        else            a[i] = abs(min(b[pl] - i,i - b[pl - 1]));        printf("%d ",a[i]);    }    return 0;}