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37 lines
662 B
C++
37 lines
662 B
C++
#include <iostream>
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using std::cin;
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using std::cout;
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using std::endl;
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int n, a[20][20], ans;
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bool vis[20];
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void dfs(int pos, int val) {
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while (vis[pos]) pos++;
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if (pos == n + 1) {
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ans = std::max(ans, val);
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return;
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}
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for (int i = pos + 1; i <= n; i++) {
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if (vis[i]) continue;
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vis[i] = true;
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dfs(pos + 1, val ^ a[i][pos]);
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vis[i] = false;
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}
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}
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int main() {
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cin >> n;
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n <<= 1;
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for (int i = 1; i <= n; i++) {
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for (int j = i + 1; j <= n; j++) {
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cin >> a[i][j];
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a[j][i] = a[i][j];
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}
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}
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dfs(1, 0);
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cout << ans << endl;
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return 0;
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}
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