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#include <bits/stdc++.h>
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using namespace std;
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const int N = 110;
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typedef long long LL;
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// TLE 超时,看来，还是递推更安全些
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int n;
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LL res, sum;
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int st[N];
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void dfs(int u) {
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if (u == n + 1) {
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res++;
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return;
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}
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for (int i = 1; i <= n; i++)
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if (!st[i] && u != i) {
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st[i] = true;
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dfs(u + 1);
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st[i] = false;
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}
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}
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int main() {
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int m;
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scanf("%d", &m);
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while (m--) {
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scanf("%d", &n);
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memset(st, 0, sizeof st);
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sum = 1;
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dfs(1);
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//总次数
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for (int i = 1; i <= n; i++) sum = sum * i;
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//比率
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printf("%.2lf%%\n", (double)res / sum * 100);
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}
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return 0;
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}
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