CCF老爷机会放O(nm^3)过吗

#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
#define ll long long
#define ull unsigned long long
#define Max(_A, _B) (_A > _B ? _A : _B)
#define Min(_A, _B) (_A < _B ? _A : _B)
const int md = 1e9 + 7, maxn = 1007;
int n, m, K;
int read() {
    int s = 0; char c = getchar();
    while (c > '9' || c < '0') c = getchar();
    while (c >= '0' && c <= '9') s = s * 10 + c - '0', c = getchar();
    return s;
}
char A[maxn], B[maxn];
ll ans;
ll f[2][maxn][201];
int main(){
    n = read(), m = read(), K = read();
    scanf("%s", A + 1); scanf("%s", B + 1);
    f[0][0][0] = 1;
    for (int i = 1; i <= n; i++) f[0][i][0] = 1;
    for (int t = 1; t <= K; t++) {
        for (int i = t; i <= n; i++) {
            for (int j = t; j <= Min(i, m); j++) {
                f[t&1][i][j] = f[t&1][i - 1][j];
                for (int len = 1; len <= j - t + 1; len++) {
                    if (A[i - len + 1] == B[j - len + 1]) {
                        f[t&1][i][j] += f[(t&1)^1][i - len][j - len];
                        f[t&1][i][j] %= md;
                    } else break;
                }
            }
        }
    }
    printf("%lld\n", f[K&1][n][m] % md);
}