2034 人见人爱A-B

#include<iostream>using namespace std;int main(){int n, m;int a[100], b[100], c[100];while (cin >> n >> m){int k=0;if (n == 0 && m == 0)break;for (int i = 0; i < n; ++i)cin >> a[i];for (int i = 0; i < m; ++i)cin >> b[i];for (int i = 0; i < n; ++i){int t = 0;for (int j = 0; j < m; ++j){if (a[i] == b[j]){t = 1;break;}}if (t == 0)c[k++] = a[i];}if (k == 0)cout << "NULL";else {int p;for (int i = 0; i < k; ++i)for (int j = i + 1; j < k; ++j){if (c[i]>c[j]){p = c[i];c[i] = c[j];c[j] = p;}}for (int i = 0; i < k; ++i)cout << c[i] << ' ';}cout << endl;}return 0;}

刚开始用vector做，很麻烦，不如直接用数组方便，数组可以直接用来赋值，可以直接改变数组元素，方便排序