原题链接：http://www.lydsy.com/JudgeOnline/problem.php?id=2761
简单题, 练习一下stl。。
1 #include<algorithm> 2 #include<iostream> 3 #include<cstdlib> 4 #include<cstdio> 5 #include<vector> 6 #include<set> 7 using std::set; 8 using std::vector; 9 int main() { 10 #ifdef LOCAL 11 freopen("in.txt", "r", stdin); 12 freopen("out.txt", "w+", stdout); 13 #endif 14 int t, n, v; 15 scanf("%d", &t); 16 while (t--) { 17 set<int> ret; 18 vector<int> ans; 19 scanf("%d %d", &n, &v); 20 ret.insert(v), ans.push_back(v); 21 for (int i = 1; i < n; i++) { 22 scanf("%d", &v); 23 if (!ret.count(v)) ret.insert(v), ans.push_back(v); 24 } 25 n = ans.size(); 26 for (int i = 0; i < n; i++) { 27 printf("%d%c", ans[i], i < n - 1 ? ' ' : ' '); 28 } 29 } 30 return 0; 31 }