题意

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Sol

莫队板子题。。

维护出每个位置开始的字符串\(mod P\)的结果，记为\(S_i\)

两个位置\(l, r\)满足条件当且仅当\(S_l - S_r = 0\)，也就是\(S_l = S_r\)

离散化之后直接上莫队就行了

对\(2, 5\)特判一下，因为2/5是10的因子，可能导致答案变大。直接维护\(0/5\)的出现次数就可以了

考场上一高兴写了三个Subtask。。

#include <bits/stdc++.h>

#define LL long long

using namespace std;

const int MAXN = 1e6 + 10;

int mod;

template <typename A, typename B>

inline void mul2(A &x, B y) {

    x = 1ll * x * y % mod;

}

template <typename A, typename B>

inline int mul(A x, B y) {

    return 1ll * x * y % mod;

}

template <typename A, typename B>

inline int add(A x, B y) {

    return x + y >= mod ? x + y - mod : x + y;

}

inline int read() {

    char c = getchar();

    int x = 0, f = 1;

    while (c < '0' || c > '9') {

        if (c == '-')

            f = -1;

        c = getchar();

    }

    while (c >= '0' && c <= '9') x = x * 10 + c - '0', c = getchar();

    return x * f;

}

int N, Q, belong[MAXN], block, l, r;

LL now, ans[MAXN];

char s[MAXN];

namespace Sub3 {

int pro[MAXN], num, date[MAXN], cnt[MAXN];

void Des() {

    for (int i = 1; i <= N + 1; i++) date[++num] = pro[i];

    sort(date + 1, date + num + 1);

    num = unique(date + 1, date + num + 1) - date - 1;

    for (int i = 1; i <= N + 1; i++) pro[i] = lower_bound(date + 1, date + num + 1, pro[i]) - date;

}

struct Query {

    int l, r, id;

    bool operator<(const Query &rhs) const {

        return belong[l] == belong[rhs.l] ? r < rhs.r : belong[l] < belong[rhs.l];

    }

} q[MAXN];

void Add(int x) {

    now += cnt[x];

    cnt[x]++;

}

void Delet(int x) {

    cnt[x]--;

    now -= cnt[x];

}

void solve() {

    block = sqrt(N);

    for (int i = 1; i <= N; i++) belong[i] = (i - 1) / block + 1;

    for (int i = N, base = 1; i >= 1; i--, mul2(base, 10)) pro[i] = add(pro[i + 1], mul((s[i] - '0'), base));

    Des();

    Q = read();

    for (int i = 1; i <= Q; i++) q[i].l = read(), q[i].r = read() + 1, q[i].id = i;

    sort(q + 1, q + Q + 1);

    l = 1, r = 0;

    for (int i = 1; i <= Q; i++) {

        while (r < q[i].r) Add(pro[++r]);

        while (r > q[i].r) Delet(pro[r--]);

        while (l < q[i].l) Delet(pro[l++]);

        while (l > q[i].l) Add(pro[--l]);

        ans[q[i].id] = now;

    }

    for (int i = 1; i <= Q; i++) cout << ans[i] << '\n';

}

}  // namespace Sub3

namespace Sub1 {

int cnt[MAXN], a[MAXN];

struct Query {

    int l, r, id;

    bool operator<(const Query &rhs) const {

        return belong[l] == belong[rhs.l] ? r < rhs.r : belong[l] < belong[rhs.l];

    }

} q[MAXN];

void Add(int x, int opt) {

    if (opt) {

        if (x == 0)

            now += r - l + 1;

    } else {

        now += cnt[0];

    }

    cnt[x]++;

}

void Delet(int x, int opt) {

    cnt[x]--;

    if (opt) {

        if (x == 0)

            now -= r - l + 1;

    } else {

        now -= cnt[0];

    }

}

void solve() {

    block = sqrt(N);

    for (int i = 1; i <= N; i++) belong[i] = (i - 1) / block + 1, a[i] = (s[i] - '0') % 2;

    Q = read();

    for (int i = 1; i <= Q; i++) q[i].l = read(), q[i].r = read(), q[i].id = i;

    sort(q + 1, q + Q + 1);

    l = 1, r = 0;

    for (int i = 1; i <= Q; i++) {

        while (r < q[i].r) Add(a[++r], 1);

        while (r > q[i].r) Delet(a[r--], 1);

        while (l < q[i].l) Delet(a[l++], 0);

        while (l > q[i].l) Add(a[--l], 0);

        ans[q[i].id] = now;

    }

    for (int i = 1; i <= Q; i++) cout << ans[i] << '\n';

}

}

namespace Sub2 {

int cnt[MAXN], a[MAXN], len[MAXN];

struct Query {

	int l, r, id;

	bool operator < (const Query &rhs) const {

		return belong[l] == belong[rhs.l] ? r < rhs.r : belong[l] < belong[rhs.l];

	}

}q[MAXN];

void Add(int x, int opt, int pos) {

	cnt[x]++;

	if(opt) {

		if(x == 0 || x == 5) now += r - l + 1;

	} else {

		now += cnt[0] + cnt[5];

	}

}

void Delet(int x, int opt, int pos) {

	if(opt) {

		if(x == 0 || x == 5) now -= r - l + 1;

	} else {

		now -= cnt[0] + cnt[5];

	}

	cnt[x]--;

}

void solve() {

	block = sqrt(N);

	for(int i = 1; i <= N; i++) belong[i] = (i - 1) / block + 1, a[i] = s[i] - '0';

	Q = read();

	for(int i = 1; i <= Q; i++) q[i].l = read(), q[i].r = read(), q[i].id = i;

	sort(q + 1, q + Q + 1);

	l = 1, r = 0;

	for(int i = 1; i <= Q; i++) {

		while(l > q[i].l)

			--l, Add(a[l], 0, l);

		while(r > q[i].r)

			Delet(a[r], 1, r), r--;

		while(l < q[i].l)

			Delet(a[l], 0, l), l++;

		while(r < q[i].r)

			++r, Add(a[r], 1, r);

		ans[q[i].id] = now;

	}

	for(int i = 1; i <= Q; i++) cout << ans[i] << '\n';

}

}

int main() {

    mod = read();

    scanf("%s", s + 1);

    N = strlen(s + 1);

    if (mod == 2)

        Sub1::solve();

    else if (mod == 5)

        Sub2::solve();

    else

        Sub3::solve();

    return 0;

}

/*

11

1211

1

1 4

*/