【POJ2926】Requirements【二进制】【最大曼哈顿距离】

【题目链接】

手被烫伤了，只能一只手敲题了，随便敲个短的。

论文题，见《浅谈信息学竞赛中的“0”和“1”》武森

/* Pigonometry */#include <cstdio>#include <algorithm>using namespace std;typedef double DB;const int maxn = 100005, maxd = 7, inf = 0x3f3f3f3f;int n, sgn[maxd];struct _data {DB d[maxd];} p[maxn];int main() {scanf("%d", &n);for(int i = 1; i <= n; i++) for(int j = 1; j <= 5; j++) scanf("%lf", &p[i].d[j]);DB ans = -1; int maxk = 1 << 5;for(int k = 0; k < maxk; k++) {DB mi = inf, mx = -inf;for(int i = 1; i <= 5; i++) sgn[i] = (k & (1 << (i - 1))) ? 1 : -1;for(int i = 1; i <= n; i++) {DB now = 0;for(int j = 1; j <= 5; j++) now += sgn[j] * p[i].d[j];mi = min(mi, now);mx = max(mx, now);}ans = max(ans, mx - mi);}printf("%.2f\n", ans);return 0;}