Longest Common subsequence of N strings

#include <cstdio>#include <cstring>#include <algorithm>using std::max;const int MAXF = 1000010;const int MAXN = 110;int n;int base[MAXN], len[MAXN], pos[MAXN];char ans;char f[MAXF];char words[MAXN][MAXN];void solve(){    int idx = 0;    for (int i = 0; i < n; i++){        idx += (pos[i] - 1) * base[i];    }    bool same = true, has_one = false;    for (int i = 1; i < n; i++) {        if (words[i][pos[i] - 1] != words[0][pos[0] - 1]) {            same = false;            break;        }        if (pos[i] == 1) {            has_one = true;        }    }    if (same) {        if (has_one) {            f[idx] = 1; } else {            int p_idx = idx;            for (int i = 0; i < n; i++) {                p_idx -= base[i];            }            f[idx] = f[p_idx] + 1;        }    }      else {    for (int i = 0; i < n; i++)     {            if (pos[i] == 1) continue;            f[idx] = max(f[idx], f[idx - base[i]]);    }  }    ans = max(ans, f[idx]);}void dp(int p){    if (p == n)     {        return solve();    }    for (int i = 1; i <= len[p]; i++) {        pos[p] = i;        dp(p + 1);    }}int main(){    scanf("%d", &n);    for (int i = 0; i < n; i++) {        scanf("%s", words[i]);        len[i] = strlen(words[i]);    }    base[0] = 1;    for (int i = 1; i < n; i++) {        base[i] = base[i - 1] * len[i - 1];    }    dp(0);    printf("%d\n", ans);    return 0;}