不知道是自己哪里写挂了还是思路不对/dk。

#include <iostream>
using namespace std;
const int MAX_SIZE = 2e7;
#define int long long
namespace FastIO
{
template <typename T = int>
inline T read() {
    T s = 0, w = 1;
    char c = getchar();
    while (!isdigit(c)) {
        if (c == '-') w = -1;
        c = getchar();
    }
    while (isdigit(c)) s = (s << 1) + (s << 3) + (c ^ 48), c = getchar();
    return s * w;
}
template <typename T>
inline void read(T &s) {
    s = 0;
    int w = 1;
    char c = getchar();
    while (!isdigit(c)) {
        if (c == '-') w = -1;
        c = getchar();
    }
    while (isdigit(c)) s = (s << 1) + (s << 3) + (c ^ 48), c = getchar();
    s = s * w;
}
template <typename T, typename... Args>
inline void read(T &x, Args &...args) {
    read(x), read(args...);
}
template <typename T>
inline void write(T x, char ch) {
    if (x < 0) x = -x, putchar('-');
    static char stk[25];
    int top = 0;
    do {
        stk[top++] = x % 10 + '0', x /= 10;
    } while (x);
    while (top) putchar(stk[--top]);
    putchar(ch);
    return;
}
}  // namespace FastIO
using namespace FastIO;

struct SegTree {
    int lc, rc;
    int sum;
    int counter;
};
SegTree seg[(MAX_SIZE << 1) + 10];

int tot;
int build() {
    ++tot;
    seg[tot].sum = seg[tot].lc = seg[tot].rc = seg[tot].counter = 0;
    return tot;
}
void insert(int p, int l, int r, int val, int data) {
    if (l == r) {
        seg[p].counter += data;
        seg[p].sum += data * (val - 1);
        return;
    }
    int mid = (l + r) >> 1;
    if (val <= mid) {
        if (!seg[p].lc) seg[p].lc = build();
        insert(seg[p].lc, l, mid, val, data);
    } else {
        if (!seg[p].rc) seg[p].rc = build();
        insert(seg[p].rc, mid + 1, r, val, data);
    }
    seg[p].counter = seg[seg[p].lc].counter + seg[seg[p].rc].counter;
    seg[p].sum = seg[seg[p].lc].sum + seg[seg[p].rc].sum;
    return;
}
int GetAns(int tl, int tr, int siz, int p) {
    if (!p || !siz) return 0;
    if (tl == tr) {
        return seg[p].sum;
    }
    int val = 0;
    int mid = (tl + tr) >> 1;
    if (siz >= seg[seg[p].rc].counter) {
        val += seg[seg[p].rc].sum;
        val += GetAns(tl, mid, siz - seg[seg[p].rc].counter, seg[p].lc);
    } else {
        val += GetAns(mid + 1, tr, siz, seg[p].rc);
    }
    return val;
}
const int MAX_NUM = 1e9 + 10;
const int MAX = 5.1e5;
int ori[MAX];
signed main() {
    tot = 0;
    int root = build();
    int n, k, Q;
    read(n, k, Q);
    while (Q--) {
        int x = read();
        int y = read();
        if (ori[x] != 0) {
            insert(root, 1, MAX_NUM, ori[x] + 1, -1);
        }
        ori[x] = y;
        insert(root, 1, MAX_NUM, ori[x] + 1, 1);
        int ans = GetAns(1, MAX_NUM, k, root);
        printf("%lld\n", ans);
    }
    return 0;
}