Description
给定用无向网表示你所在学校的校园景点平面图(图中顶点表示主要景点,存放景点的编号、名称、简介等信息,图中的边表示景点间的道路,存放路径长度等信息)。要求能够回答有关景点介绍、游览路径等问题。
Input
输入第一行为测试数据组数。每组数据第一行为3个整数n(2<=n<=200)、m(0<=m<=300)、k(0<=k<=1000),分别代表景点数、道路数和操作数。接下来1行n个整数p(1<=p<=100)代表每个景点好玩程度,景点编号从1开始。在接下来有m行,每行3个整数分别代表起点、终点、长度l(1<=l<=100)。然后k行,第一个整数q为操作类型,有如下几种输入:
0 x h:将x和与x直接连通的景点的好玩度提高h(1<=h<=100)。
1 x:查询景点x的好玩度。
2 x y l:在x和y之间建立了一条长度为l(1<=l<=100)的通路。(输入保证建立道路的次数不超过10次)。
3 x y:查询x到y的最短路的距离,不连通输出“No such path.”。
Output
对于q为1和q为3的查询,每个查询输出一行,格式见样例。
Sample Input
1
5 3 5
75 34 22 83 77
1 3 40
4 5 9
5 2 52
1 5
0 4 2
3 1 4
2 3 5 77
3 1 4
Sample Output
Case #1:
5 : 77
No such path.
1 -> 4 : 126
HINT
考察知识点:图的遍历、最短路径算法、图的修改等,时间复杂度O(n3)
Append Code
析:要最短路径么,我们可以用Floyd来最最短长度,然后在加边时,也要再用这个算法,不断更新,这个好多坑,主要的就是可能有重复边,还有同一条边可能有多个权值,
我们要选最优的,不要重复加边。
代码如下:
#pragma comment(linker, "/STACK:1024000000,1024000000") #include <cstdio> #include <string> #include <cstdlib> #include <cmath> #include <iostream> #include <cstring> #include <set> #include <queue> #include <algorithm> #include <vector> #include <map> #include <cctype> #include <cmath> #include <stack> #define debug puts("+++++") //#include <tr1/unordered_map> #define freopenr freopen("in.txt", "r", stdin) #define freopenw freopen("out.txt", "w", stdout) using namespace std; //using namespace std :: tr1; typedef long long LL; typedef pair<int, int> P; const int INF = 0x3f3f3f3f; const double inf = 0x3f3f3f3f3f3f; const LL LNF = 0x3f3f3f3f3f3f; const double PI = acos(-1.0); const double eps = 1e-8; const int maxn = 200 + 5; const LL mod = 1e3 + 7; const int N = 1e6 + 5; const int dr[] = {-1, 0, 1, 0, 1, 1, -1, -1}; const int dc[] = {0, 1, 0, -1, 1, -1, 1, -1}; const char *Hex[] = {"0000", "0001", "0010", "0011", "0100", "0101", "0110", "0111", "1000", "1001", "1010", "1011", "1100", "1101", "1110", "1111"}; inline LL gcd(LL a, LL b){ return b == 0 ? a : gcd(b, a%b); } inline int gcd(int a, int b){ return b == 0 ? a : gcd(b, a%b); } inline int lcm(int a, int b){ return a * b / gcd(a, b); } int n, m; const int mon[] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; const int monn[] = {0, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; inline int Min(int a, int b){ return a < b ? a : b; } inline int Max(int a, int b){ return a > b ? a : b; } inline LL Min(LL a, LL b){ return a < b ? a : b; } inline LL Max(LL a, LL b){ return a > b ? a : b; } inline bool is_in(int r, int c){ return r >= 0 && r < n && c >= 0 && c < m; } set<int> sets[maxn]; set<int>::iterator it; int dp[maxn][maxn]; int a[maxn]; int main() { int T; cin >> T; int q; for(int kase = 1; kase <= T; ++kase){ scanf("%d %d %d", &n, &m, &q); //for(int i = 1; i <= n; ++i) G[i].clear(); for(int i = 1; i <= n; ++i) for(int j = 1; j <= n; ++j) dp[i][j] = INF; for(int i = 1; i <= n; ++i) scanf("%d", a + i), sets[i].clear(), sets[i].insert(i); int u, v, c; for(int i = 0; i < m; ++i) { scanf("%d %d %d", &u, &v, &c); sets[u].insert(v); sets[v].insert(u); if (dp[u][v] > c) dp[u][v] = dp[v][u] = c; } for(int k = 1; k <= n; ++k) for (int i = 1; i <= n; ++i) for (int j = 1; j <= n; ++j) if (dp[i][j] > dp[i][k] + dp[k][j]) dp[i][j] = dp[i][k] + dp[k][j]; printf("Case #%d:\n", kase); int x; for (int p = 0; p < q; ++p) { scanf("%d", &x); if (!x){ scanf("%d %d", &u, &v); for (it = sets[u].begin(); it != sets[u].end(); ++it) a[(*it)] += v; } else if(x == 1) { scanf("%d", &u); printf("%d : %d\n", u, a[u]); } else if(x == 2) { scanf("%d %d %d", &u, &v, &c); sets[u].insert(v); sets[v].insert(u); if(dp[u][v] <= c) continue; dp[u][v] = dp[v][u] = c; for(int i = 1; i <= n; ++i) for(int j = 1; j <= n; ++j) if (dp[i][j] > dp[i][u] + dp[u][j]) dp[i][j] = dp[i][u] + dp[u][j]; for(int i = 1; i <= n; ++i) for(int j = 1; j <= n; ++j) if (dp[i][j] > dp[i][v] + dp[v][j]) dp[i][j] = dp[i][v] + dp[v][j]; } else if(x == 3) { scanf("%d %d", &u, &v); if (dp[u][v] == INF) printf("No such path.\n"); else printf("%d -> %d : %d\n", u, v, dp[u][v]); } } } return 0; }