Total Submission(s): 3780 Accepted Submission(s): 1298
Problem Description
There are N villages, which are numbered from 1 to N, and you should build some roads such that every two villages can connect to each other. We say two village A and B are connected, if and only if there is a road between A and B, or there exists a village C such that there is a road between A and C, and C and B are connected.
We know that there are already some roads between some villages and your job is the build some roads such that all the villages are connect and the length of all the roads built is minimum.
We know that there are already some roads between some villages and your job is the build some roads such that all the villages are connect and the length of all the roads built is minimum.
Input
The first line is an integer N (3 <= N <= 100), which is the number of villages. Then come N lines, the i-th of which contains N integers, and the j-th of these N integers is the distance (the distance should be an integer within [1, 1000]) between village i and village j.
Then there is an integer Q (0 <= Q <= N * (N + 1) / 2). Then come Q lines, each line contains two integers a and b (1 <= a < b <= N), which means the road between village a and village b has been built.
Then there is an integer Q (0 <= Q <= N * (N + 1) / 2). Then come Q lines, each line contains two integers a and b (1 <= a < b <= N), which means the road between village a and village b has been built.
Output
You should output a line contains an integer, which is the length of all the roads to be built such that all the villages are connected, and this value is minimum.
#include<iostream>
#include<string.h>
using namespace std;
#define infinity 123456789
#define max_vertexes 100
typedef int Graph[max_vertexes][max_vertexes];
Graph G;
int total;
int lowcost[max_vertexes],closeset[max_vertexes],used[max_vertexes];
int father[max_vertexes];
void prim(Graph G,int vcount)
{
int i,j,k;
int min = infinity;
for (i=0;i<vcount;i++)
{
lowcost[i]=G[0][i];
closeset[i]=0;
used[i]=0;
father[i]=-1;
}
used[0]=1;
for (i=1;i<vcount;i++)
{
j=0;
while (used[j]) j++;
min = lowcost[j];
for (k=0;k<vcount;k++)
if ((!used[k])&&(lowcost[k]<min))
{
min =lowcost[k];
j=k;
}
father[j]=closeset[j];
used[j]=1;
total += min;
for (k=0;k<vcount;k++)
if (!used[k]&&(G[j][k]<lowcost[k]))
{
lowcost[k]=G[j][k];
closeset[k]=j;
}
}
}
int main()
{
int N,i,j,Q;
int x,y;
while(cin>>N)
{
total = 0;
for(i =0; i< N;i++)
{
for(j = 0;j < N; j ++)
cin>>G[i][j];
}
cin>>Q;
for(i = 0; i < Q; i ++)
{
cin>>x>>y;
G[x-1][y-1] = 0;
G[y-1][x-1] = 0;
}
prim(G,N);
cout<< total<<endl;
}
return 0;
}
#include<string.h>
using namespace std;
#define infinity 123456789
#define max_vertexes 100
typedef int Graph[max_vertexes][max_vertexes];
Graph G;
int total;
int lowcost[max_vertexes],closeset[max_vertexes],used[max_vertexes];
int father[max_vertexes];
void prim(Graph G,int vcount)
{
int i,j,k;
int min = infinity;
for (i=0;i<vcount;i++)
{
lowcost[i]=G[0][i];
closeset[i]=0;
used[i]=0;
father[i]=-1;
}
used[0]=1;
for (i=1;i<vcount;i++)
{
j=0;
while (used[j]) j++;
min = lowcost[j];
for (k=0;k<vcount;k++)
if ((!used[k])&&(lowcost[k]<min))
{
min =lowcost[k];
j=k;
}
father[j]=closeset[j];
used[j]=1;
total += min;
for (k=0;k<vcount;k++)
if (!used[k]&&(G[j][k]<lowcost[k]))
{
lowcost[k]=G[j][k];
closeset[k]=j;
}
}
}
int main()
{
int N,i,j,Q;
int x,y;
while(cin>>N)
{
total = 0;
for(i =0; i< N;i++)
{
for(j = 0;j < N; j ++)
cin>>G[i][j];
}
cin>>Q;
for(i = 0; i < Q; i ++)
{
cin>>x>>y;
G[x-1][y-1] = 0;
G[y-1][x-1] = 0;
}
prim(G,N);
cout<< total<<endl;
}
return 0;
}
]]>
鍜屽叾浠栫敤鐭╅樀鐨勭◢鏈変笉鍚?br>
//閲囩敤涓寸晫琛ㄧ殑褰㈠紡 浣嗘槸鐢ㄦ暟緇勬潵瀹炵幇 鍏朵腑瑕佺敤C++ 鐨勯槦鍒梥tl 灝介噺浣夸唬鐮佺殑鍙敤搴︽彁楂?br>// 緗戜笂澶у閲囩敤 涓存帴鐭╅樀鐨勬柟寮忔潵鍋氱殑
# include<cstdio>
# include<iostream>
# include<queue>
# include<vector>
using namespace std;
const int maxn = 510;
struct graph
{
int edge[maxn][maxn];//edge[i][j] 琛ㄧず絎琲涓妭鐐?nbsp;絎?nbsp;j+1涓竟 鍏跺艱〃紺鴻杈圭殑欏剁偣
int outdegree[maxn +1];// 欏剁偣鐨勫嚭搴?/span>
int nvert ;//鑺傜偣鏁?/span>
int nedge;// 杈規暟 娉ㄦ剰瀹氱偣鎴戜滑鏄粠1 寮濮嬬畻 鐒跺悗杈規暟鎴戜滑鏄粠0 寮濮嬬殑
};
typedef struct graph GRAPH;
struct graph g;// 鍥劇殑鍏ㄥ眬鍙橀噺
void init_graph()
{
int i;
g.nedge = 0;
g.nvert = 0;
for (i = 1; i <=maxn ; i ++ ) g.outdegree[i] = 0;
}
void inert_graph(int x,int y,bool flag )
{
//if(g.outdegree[x] > maxn )//瀹歸敊
g.edge[x][g.outdegree[x]] = y;
g.outdegree[x] ++;//鍑哄害 + 1
if (flag == false) inert_graph(y,x,true);//濡傛灉鏄棤鍚戝浘 鍙嶅悜涔熻鍔?/span>
else g.nedge ++;//杈規暟 ++
}
int read_graph(bool flag) //flag 鐢ㄦ潵鎺у埗 鏄惁鏄湁鍚戝浘
{
//榪欓噷鍙互鏍規嵁瀹為檯鎯呭喌娣誨姞浠ｇ爜
int n,i;
int x,y;
init_graph();
if (scanf("%d%d",&g.nvert,&n)==EOF)
return 0;
for (i =1; i <= n; i ++)
{
scanf("%d%d",&x,&y);
inert_graph(x,y,true);//鏄湁鍚戝浘
}
return 1;
}
//鎷撴墤鎺掑簭 涓嬮潰鏄痶op 鎺掑簭鎵闇瑕佺殑涓滀笢
int sorted[maxn];
int indegree[maxn]; //璁＄畻鍏ュ害
int visted[maxn];
void topsorted()
{
queue<int> zeroin;
int x,y;
int i,j;
//鍒濊瘯鍖?nbsp;鍏ュ害鏁扮粍
for (i = 1; i <= maxn ; i ++) indegree[i] = 0;
//璁＄畻鍏ュ害
for (i = 1; i <= g.nvert ; i++ )
for (j = 0; j < g.outdegree[i]; j++) // 鎵浠ヨ繖閲屾垜浠槸浠?nbsp;0 寮濮?/span>
indegree[g.edge[i][j]] ++;
for(i = 1; i <= g.nvert ; i ++)
{
//for (i = g.nvert; i >= 1 ; i --)
if (indegree[i] == 0) zeroin.push(i);
}
j = 0;
memset(visted,0,sizeof(visted));
for(j = 1;j <= g.nvert;j++)// 鍥犱負棰樼洰鐨勫師鍥?鏀懼純闃熷垪
{
for(i = 1;i<=g.nvert;i++ )
{
if(visted[i] == 0 && indegree[i] == 0)
{
sorted[j] = i,visted[i] = 1;
for(int k = 0;k< g.outdegree[i];k++)
indegree[g.edge[i][k]]--;
break;
}
}
}
//if(j != g.nvert) ;//琛ㄦ槑鍙湁 j涓畾鐐規壘鍒?/span>
}
void print_graph()
{
int i,j;
for (i = 1; i <= g.nvert; i ++)
{
printf("%d: ",i);
for (j = 0; j < g.nvert ; j ++)
printf(" %d",g.edge[i][j]);
printf("\n");
}
}
int main()
{
freopen("in.txt","r",stdin);
while (read_graph(true)==1)
{
topsorted();
//print_graph();
for (int i = 1; i <= g.nvert; i ++)
printf(i==1?"%d":" %d",sorted[i]);
printf("\n");
}
return 0;
}
# include<cstdio>
# include<iostream>
# include<queue>
# include<vector>
using namespace std;
const int maxn = 510;
struct graph
{
int edge[maxn][maxn];//edge[i][j] 琛ㄧず絎琲涓妭鐐?nbsp;絎?nbsp;j+1涓竟 鍏跺艱〃紺鴻杈圭殑欏剁偣
int outdegree[maxn +1];// 欏剁偣鐨勫嚭搴?/span>
int nvert ;//鑺傜偣鏁?/span>
int nedge;// 杈規暟 娉ㄦ剰瀹氱偣鎴戜滑鏄粠1 寮濮嬬畻 鐒跺悗杈規暟鎴戜滑鏄粠0 寮濮嬬殑
};
typedef struct graph GRAPH;
struct graph g;// 鍥劇殑鍏ㄥ眬鍙橀噺
void init_graph()
{
int i;
g.nedge = 0;
g.nvert = 0;
for (i = 1; i <=maxn ; i ++ ) g.outdegree[i] = 0;
}
void inert_graph(int x,int y,bool flag )
{
//if(g.outdegree[x] > maxn )//瀹歸敊
g.edge[x][g.outdegree[x]] = y;
g.outdegree[x] ++;//鍑哄害 + 1
if (flag == false) inert_graph(y,x,true);//濡傛灉鏄棤鍚戝浘 鍙嶅悜涔熻鍔?/span>
else g.nedge ++;//杈規暟 ++
}
int read_graph(bool flag) //flag 鐢ㄦ潵鎺у埗 鏄惁鏄湁鍚戝浘
{
//榪欓噷鍙互鏍規嵁瀹為檯鎯呭喌娣誨姞浠ｇ爜
int n,i;
int x,y;
init_graph();
if (scanf("%d%d",&g.nvert,&n)==EOF)
return 0;
for (i =1; i <= n; i ++)
{
scanf("%d%d",&x,&y);
inert_graph(x,y,true);//鏄湁鍚戝浘
}
return 1;
}
//鎷撴墤鎺掑簭 涓嬮潰鏄痶op 鎺掑簭鎵闇瑕佺殑涓滀笢
int sorted[maxn];
int indegree[maxn]; //璁＄畻鍏ュ害
int visted[maxn];
void topsorted()
{
queue<int> zeroin;
int x,y;
int i,j;
//鍒濊瘯鍖?nbsp;鍏ュ害鏁扮粍
for (i = 1; i <= maxn ; i ++) indegree[i] = 0;
//璁＄畻鍏ュ害
for (i = 1; i <= g.nvert ; i++ )
for (j = 0; j < g.outdegree[i]; j++) // 鎵浠ヨ繖閲屾垜浠槸浠?nbsp;0 寮濮?/span>
indegree[g.edge[i][j]] ++;
for(i = 1; i <= g.nvert ; i ++)
{
//for (i = g.nvert; i >= 1 ; i --)
if (indegree[i] == 0) zeroin.push(i);
}
j = 0;
memset(visted,0,sizeof(visted));
for(j = 1;j <= g.nvert;j++)// 鍥犱負棰樼洰鐨勫師鍥?鏀懼純闃熷垪
{
for(i = 1;i<=g.nvert;i++ )
{
if(visted[i] == 0 && indegree[i] == 0)
{
sorted[j] = i,visted[i] = 1;
for(int k = 0;k< g.outdegree[i];k++)
indegree[g.edge[i][k]]--;
break;
}
}
}
//if(j != g.nvert) ;//琛ㄦ槑鍙湁 j涓畾鐐規壘鍒?/span>
}
void print_graph()
{
int i,j;
for (i = 1; i <= g.nvert; i ++)
{
printf("%d: ",i);
for (j = 0; j < g.nvert ; j ++)
printf(" %d",g.edge[i][j]);
printf("\n");
}
}
int main()
{
freopen("in.txt","r",stdin);
while (read_graph(true)==1)
{
topsorted();
//print_graph();
for (int i = 1; i <= g.nvert; i ++)
printf(i==1?"%d":" %d",sorted[i]);
printf("\n");
}
return 0;
}
]]>