【超长篇！一篇文章讲懂生成函数！】【那些你可能忘记了的算法5】生成函数&例题&卷积-CSDN博客

#include <bits/stdc++.h>
#define LL long long
using namespace std;
const LL P = 10007;
char s[510];
LL qpow(LL a, LL b) {
    int res = 1;
    for (; b; b >>= 1, a = a * a % P)
        if (b & 1) res = (res * a) % P;
    return res;
}
int main() {
    scanf("%s", s);
    LL n = 0, len = strlen(s);
    for (int i = 0; i < len; i++)
        n = (n * 10 % P + s[i] - '0') % P;
    LL ans = n * (n + 1) % P * (n + 2) % P * qpow(6LL, P - 2) % P;
    printf("%lld\n", ans);
    return 0;
}