#include <algorithm>
#include <iostream>
#include <cstdio>
#include <cstring>
#include <queue>
#define LL long long
#define pii pair<int, int>
#define lowbit(x) (x << 1)
#define ls(x) (x << 1)
#define rs(x) ((x << 1) | 1)
#define db double
#define pli pair<LL, int>
using namespace std;
const int maxn = 100010;
struct node {LL val;int pos;bool operator < (const node & rhs) const {return val > rhs.val;}
};
priority_queue<node> Q;
LL dp[maxn], a[maxn];
int q[maxn];
bool v[maxn];
LL val[maxn];
LL sum[maxn];
void change(LL x, int y) {Q.push((node){x, y});val[y] =  x;
}
int main() {int n;LL m;scanf("%d%lld", &n, &m);for (int i = 1; i <= n; i++) {scanf("%lld", &a[i]);sum[i] = sum[i - 1] + a[i];}int l = 1, r = 1, ans = 0, pos = 0;dp[1] = a[1];q[1] = 1;if(a[1] > m) ans = -1;for (int i = 2; i <= n; i++) {while(sum[i] - sum[pos] > m) pos++;if(pos == i) {ans = -1;break;}while(l <= r && sum[i] - sum[q[l] - 1] > m) {v[q[l]] = 1;l++;}while(l <= r && a[q[r]] <= a[i]) {v[q[r]] = -1;r--;}if(l <= r)change(dp[q[r]] + a[i], q[r]);q[++r] = i;dp[i] = dp[pos] + a[q[l]];while(Q.size() && (v[Q.top().pos] == 1 || val[Q.top().pos] != Q.top().val)) {Q.pop();}if(Q.size()) {dp[i] = min(dp[i], Q.top().val);}}if(ans == -1) {printf("%d\n", ans);} else {printf("%lld\n", dp[n]);}
}

#include <bits/stdc++.h>
#define LL long long
#define pii pair<int, int>
#define lowbit(x) (x << 1)
#define ls(x) (x << 1)
#define rs(x) ((x << 1) | 1)
#define db double
#define pli pair<LL, int>
#include <ext/pb_ds/priority_queue.hpp>
using namespace std;
using namespace __gnu_pbds;
const int maxn = 100010;
struct node {LL val;int pos;bool operator < (const node & rhs) const {return val > rhs.val;}
};
typedef __gnu_pbds::priority_queue<node> Heap;
Heap Q;
Heap::point_iterator id[maxn];
LL dp[maxn], a[maxn];
int q[maxn];
bool v[maxn];
LL sum[maxn];
void change(LL x, int y) {if(id[y] != 0)Q.modify(id[y], (node){x, y});else id[y] = Q.push((node){x, y});
}
int main() {int n, m;//freopen("17.in", "r", stdin);scanf("%d%d", &n, &m);for (int i = 1; i <= n; i++) {scanf("%d", &a[i]);sum[i] = sum[i - 1] + a[i];}int l = 1, r = 1, ans = 0, pos = 0;dp[1] = a[1];q[1] = 1;if(a[1] > m) ans = -1;for (int i = 2; i <= n; i++) {while(sum[i] - sum[pos] > m) pos++;if(pos == i) {ans = -1;break;}while(l <= r && sum[i] - sum[q[l] - 1] > m) {v[q[l]] = 1;l++;}if(l > r) {ans = -1;break;}while(l <= r && a[q[r]] <= a[i]) {v[q[r]] = 1;r--;}
//      Q.push(make_pair(dp[pos] + a[i], a[q[l]]));
//      printf("%d\n", Q.size());if(l <= r)change(dp[q[r]] + a[i], q[r]);q[++r] = i;dp[i] = dp[pos] + a[q[l]];while(Q.size() && v[Q.top().pos]) {id[Q.top().pos] = 0;Q.pop();}if(Q.size()) {//printf("%lld %d\n", Q.top().val, Q.top().pos);dp[i] = min(dp[i], Q.top().val);}}for (int i = 1; i <= n; i++)printf("%d %lld\n", i, dp[i]);if(ans == -1) {printf("%d\n", ans);} else {printf("%lld\n", dp[n]);}
}