題目:有一個班級的學生要一起寫作業,所以他們要到一個統一的地點。現在給你他們各自的位置,
問集合地點定在哪,能够讓全部人走的總路徑長度最小。
分析:圖論、最短路。直接利用Floyd計算最短路,找到和值最小的輸出就可以。
說明:又是太長時間沒刷題了。╮(╯▽╰)╭。
#include <algorithm>
#include <iostream>
#include <string>
#include <map>
using namespace std;
int dist[23][23];
int main()
{
int n, m, u, v, d, cases = 1;
string place;
while (cin >> n >> m && n+m) {
map<int, string>nameList;
for (int i = 0; i < n; ++ i) {
cin >> place;
nameList[i] = place;
}
for (int i = 0; i < n; ++ i) {
for (int j = 0; j < n; ++ j)
dist[i][j] = 500000;
dist[i][i] = 0;
}
for (int i = 0; i < m; ++ i) {
cin >> u >> v >> d;
dist[u-1][v-1] = dist[v-1][u-1] = d;
}
for (int k = 0; k < n; ++ k)
for (int i = 0; i < n; ++ i)
for (int j = 0; j < n; ++ j)
if (dist[i][j] > dist[i][k]+dist[k][j])
dist[i][j] = dist[i][k]+dist[k][j];
int space = 0, max = 500000;
for (int i = 0; i < n; ++ i) {
int sum = 0;
for (int j = 0; j < n; ++ j)
if (i != j)
sum += dist[i][j];
if (max > sum) {
max = sum;
space = i;
}
}
cout << "Case #" << cases ++ << " : " << nameList[space] << endl;
}
return 0;
}