#include <bits/stdc++.h>

using namespace std;

const int N = 2e5 + 5;
int n, k, f[N], d[N];
char s[N];

struct INT {
    int a[N], n;
    static const int lim = 1, LIM = 10;
    void scan(int l, int r) {
        n = 0;
        int cnt = 0, res = 0, bs = 1;
        for (int i = r; i >= l; i--) {
            res += (s[i] - '0') * bs;
            bs *= 10, cnt++;
            if (cnt == 9) {
                a[n++] = res;
                cnt = 0, res = 0, bs = 1;
            }
        }
        if (res) a[n++] = res;
    }
    void print() {
        if (!n) printf("0");
        else {
            for (int i = n - 1; i >= 0; i--) printf("%d", a[i]);
        }
    }
    int & operator [] (const int & x) {
        return a[x];
    }
    INT operator + (const INT & b) const {
        INT c;
        int mx = max(n, b.n), rst = 0;
        for (int i = 0; i < mx; i++) {
            int A = 0, B = 0;
            if (i < n) A = a[i];
            if (i < b.n) B = b.a[i];
            c[i] = (rst + A + B) % LIM;
            rst = (rst + A + B) / LIM;
        }
        c.n = mx;
        if (rst) c[c.n++] = rst;
        return c;
    }
    INT & operator = (const INT & b) {
        n = b.n;
        for (int i = 0; i < n; i++) {
            a[i] = b.a[i];
        }
        return *this;
    }
    bool operator < (const INT & b) const {
        if (n != b.n) return n < b.n;
        for (int i = n - 1; i >= 0; i--) {
            if (a[i] != b.a[i]) return a[i] < b.a[i];
        }
        return 0;
    }
} a[7], sm, mn;

void dfs(int dep) {
    if (dep > k) {
        int tot = 0;
        for (int i = 1; i <= k; i++) {
            d[i] = d[i - 1] + f[i];
            tot += d[i];
        }
        if (n - tot <= 0 || ((n - tot) % (k + 1))) return;
        int l = (n - tot) / (k + 1), nw = 1;
        sm.n = 0;
        for (int i = 0; i <= k; i++) {
            a[i].scan(nw, nw + l + d[i] - 1);
            nw += l + d[i];
            sm = sm + a[i];
        }
        mn = min(mn, sm);
        return;
    }
    for (int i = -1; i <= 1; i++) {
        f[dep] = i;
        dfs(dep + 1);
    }
}

int main() {
    int T; scanf("%d", &T);
    while (T--) {
        mn.n = 1919810;
        scanf("%d%d%s", &n, &k, s + 1);
        dfs(1);
        mn.print();
        printf("\n");
    }
    return 0;
}