【Codeforces Round #428 (Div. 2) A】Arya and Bran

【Link】:

【Description】

【Solution】

傻逼题

【NumberOf WA】

【Reviw】

【Code】

#include <bits/stdc++.h>
using namespace std;
#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1
#define LL long long
#define rep1(i,a,b) for (int i = a;i <= b;i++)
#define rep2(i,a,b) for (int i = a;i >= b;i--)
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define ms(x,y) memset(x,y,sizeof x)
#define ri(x) scanf("%d",&x)
#define rl(x) scanf("%lld",&x)
#define rs(x) scanf("%s",x+1)
#define oi(x) printf("%d",x)
#define ol(x) printf("%lld",x)
#define oc putchar(' ')
#define os(x) printf(x)
#define all(x) x.begin(),x.end()
#define Open() freopen("F:\rush.txt","r",stdin)
#define Close() ios::sync_with_stdio(0)

typedef pair<int,int> pii;
typedef pair<LL,LL> pll;

const int dx[9] = {0,1,-1,0,0,-1,-1,1,1};
const int dy[9] = {0,0,0,-1,1,-1,1,-1,1};
const double pi = acos(-1.0);
const int N = 110;

int n,k;

int main(){
    //Open();
    //Close();
    ri(n),ri(k);
    int now = 0,cur = 0;
    rep1(i,1,n){
        int x;
        ri(x);
        cur+=x;
        now += min(cur,8);
        cur -= min(cur,8);
        if (now >= k){
            oi(i);puts("");
            return 0;
        }
    }
    puts("-1");
    return 0;
}