Pagini recente » Cod sursa (job #220884) | Cod sursa (job #963903) | Cod sursa (job #174896) | Cod sursa (job #840142) | Cod sursa (job #2186756)
#include<cstdio>
#include<vector>
#include<algorithm>
#define MAX_N 200000
#define MAX_M 400000
using namespace std;
struct edge {
int x, y, cost;
};
edge v[MAX_M];
int p[MAX_N + 1], h[MAX_N + 1], n, m, minCost, apmSize;
vector<pair<int,int> >apm;
void readGraph() {
FILE* fin = fopen("apm.in","r");
fscanf(fin,"%d%d",&n,&m);
for(int i = 0; i < m; i++)
fscanf(fin,"%d%d%d",&v[i].x,&v[i].y,&v[i].cost);
fclose(fin);
}
inline bool cmp(edge a, edge b) {
return a.cost < b.cost;
}
void Init(int n) {
for(int i = 1; i <= n; i++) {
p[i] = i;
h[i] = 1;
}
}
inline int Find(int x) {
int r, aux;
r = x;
while(p[r] != r)
r = p[r];
while(p[x] != r) {
aux = p[x];
p[x] = r;
x = aux;
}
return r;
}
inline void Union(int x, int y, int i) {
int rootx, rooty;
rootx = Find(x);
rooty = Find(y);
if(rootx != rooty) {
minCost += v[i].cost;
apm.push_back(make_pair(x,y));
apmSize++;
if(h[rootx] < h[rooty])
p[rootx] = rooty;
else if(h[rootx] > h[rooty])
p[rooty] = rootx;
else {
p[rootx] = rooty;
h[rooty]++;
}
}
}
void Kruskal() {
sort(v,v+m,cmp);
Init(n);
for(int i = 0; apmSize < n - 1; i++)
Union(v[i].x,v[i].y,i);
}
void printAPM() {
vector<pair<int,int> >::iterator it;
FILE* fout = fopen("apm.out","w");
fprintf(fout,"%d\n%d\n",minCost,apmSize);
for(it = apm.begin(); it != apm.end(); it++)
fprintf(fout,"%d %d\n",(*it).first,(*it).second);
fclose(fout);
}
int main() {
readGraph();
Kruskal();
printAPM();
return 0;
}