#466. 摘桃子

原创

whiteawll 2022-08-16 14:47:14 博主文章分类：练习题目 ©著作权

©著作权归作者所有：来自51CTO博客作者whiteawll的原创作品，请联系作者获取转载授权，否则将追究法律责任

#include<bits/stdc++.h>
using namespace std;

#define rep(i,l,r) for(int i=(l);i<=(r);i++)
#define per(i,l,r) for(int i=(l);i>=(r);i--)
#define ll long long
#define pii pair<int, int>
#define mset(s,t) memset(s,t,sizeof(t))
#define mcpy(s,t) memcpy(s,t,sizeof(t))
#define fi first
#define se second
#define pb push_back
#define all(x) (x).begin(),(x).end()
#define SZ(x) ((int)(x).size())
#define mp make_pair

const ll mod = 1e9 + 7;
//const ll mod = 998244353;

inline ll qmi (ll a, ll b) {
    ll ans = 1;
    while (b) {
        if (b & 1) ans = ans * a%mod;
        a = a * a %mod;
        b >>= 1;
    }
    return ans;
}
inline int read () {
    int x = 0, f = 0;
    char ch = getchar();
    while (!isdigit(ch)) f |= (ch=='-'),ch= getchar();
    while (isdigit(ch)) x = x * 10 + ch - '0', ch = getchar();
    return f?-x:x;
}
template<typename T> void print(T x) {
    if (x < 0) putchar('-'), x = -x;
    if (x >= 10) print(x/10);
    putchar(x % 10 + '0');
}
inline ll sub (ll a, ll b) {
    return ((a - b ) %mod + mod) %mod;
}
inline ll add (ll a, ll b) {
    return (a + b) %mod;
}
inline ll inv (ll a) {
    return qmi(a, mod - 2);
}
#define int long long
int l, r;
void solve() {
    // s[i] -s[j - 1] = i -j + 1;
    // s[i] - 1 = s[j - 1] + i - j
    int n, k;
    cin >> n >> k;
    vector<int> a(n + 1);
    for (int i = 1; i<= n ;i ++)
        cin >> a[i];
    vector<int> s(n + 1);
    for (int i = 1; i<= n; i ++)
        s[i]  =(s[i - 1] + a[i])%k;
    for (int i = 1; i<= n; i ++)
        s[i] = ((s[i] - i) %k + k)%k;
    map<int, int> st;
    ll ans = 0;
    st[0] = 1;
    for (int i = 1, j = 0;  i<= n ;i ++) {
        if (j <= i - k) st[s[j++]] --;
        ans += st[s[i]];
        st[s[i]] ++;
    }
    cout << ans <<endl;
}
signed main () {
    // ios::sync_with_stdio(0),cin.tie(0), cout.tie(0);
    int t;
    t =1;
    //cin >> t;
    while (t --) solve();
    return 0;
}