Codeforces Round #446 (Div. 2) B Wrath

更新往前击杀最大值，，On

#include<iostream>#include<algorithm>#include<cstdio>#include<cstdlib>#include<cstring>#include<string>#include<cmath>#include<set>#include<queue>#include<stack>#include<map>#define PI acos(-1.0)#define in freopen("in.txt", "r", stdin)#define out freopen("out.txt", "w", stdout)using namespace std;typedef long long ll;typedef unsigned long long ull;const int maxn = 1e6 + 7, maxd = (1<<18)-1, mod = 1000003;const int INF = 0x7f7f7f7f;int n;int a[maxn];int main() {    scanf("%d", &n);    for(int i = 1; i <= n; ++i) {        scanf("%d", &a[i]);    }    int ans = 0;    int j = 0;    for(int i = n; i >= 1; --i) {        if(j == 0 && a[i] != -1) {            ans++;            j = a[i];        } else if(j) {            j = max(j-1, a[i]);        } else j--;    }    cout << ans << endl;    return 0;}