A11413. Wrath
编程题
普及/提高-
知识点
题目描述
Hands that shed innocent blood!
There are $n$ guilty people in a line, the $i$ -th of them holds a claw with length $L_{i}$ . The bell rings and every person kills some of people in front of him. All people kill others at the same time. Namely, the $i$ -th person kills the $j$ -th person if and only if $j<i$ and $j>=i-L_{i}$ .
You are given lengths of the claws. You need to find the total number of alive people after the bell rings.
There are $n$ guilty people in a line, the $i$ -th of them holds a claw with length $L_{i}$ . The bell rings and every person kills some of people in front of him. All people kill others at the same time. Namely, the $i$ -th person kills the $j$ -th person if and only if $j<i$ and $j>=i-L_{i}$ .
You are given lengths of the claws. You need to find the total number of alive people after the bell rings.
输入格式
The first line contains one integer $n$ ( $1<=n<=10^{6}$ ) — the number of guilty people.
Second line contains $n$ space-separated integers $L_{1},L_{2},...,L_{n}$ ( $0<=L_{i}<=10^{9}$ ), where $L_{i}$ is the length of the $i$ -th person's claw.
Second line contains $n$ space-separated integers $L_{1},L_{2},...,L_{n}$ ( $0<=L_{i}<=10^{9}$ ), where $L_{i}$ is the length of the $i$ -th person's claw.
输出格式
Print one integer — the total number of alive people after the bell rings.
输入输出样例
输入 #1
4 0 1 0 10
输出 #1
1
输入 #2
2 0 0
输出 #2
2
输入 #3
10 1 1 3 0 0 0 2 1 0 3
输出 #3
3
说明/提示
In first sample the last person kills everyone in front of him.