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@qnighy
Created Feb 17, 2011
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As priority_queue broken, we tried implementing Dijkstra using RMQ.
#include <algorithm>
#include <cstdio>
#include <climits>
#include <vector>
using namespace std;
int main() {
while(true) {
int n,m; scanf("%d%d", &n, &m);
if(m==0) break;
vector<vector<pair<int,pair<int,int> > > > graph;
graph.resize(m);
for(int i = 0; i < n; i++) {
int a,b,c,t; scanf("%d%d%d%d", &a, &b, &c, &t); a--; b--;
graph[a].push_back(make_pair(b,make_pair(c,t)));
graph[b].push_back(make_pair(a,make_pair(c,t)));
}
int k; scanf("%d", &k);
for(int ii = 0; ii < k; ii++) {
int p,q,r; scanf("%d%d%d", &p, &q, &r); p--; q--;
const int INIT = INT_MAX/2;
const int FIN = INT_MAX/2-1;
static int segt[1<<8];
fill(segt, segt+(1<<8), INIT);
segt[p+(1<<7)] = 0;
for(int j = p+(1<<7); j > 1; j>>=1) segt[j>>1] = min(segt[j],segt[j^1]);
while(segt[1] < FIN) {
int j;
for(j = 1; j < (1<<7);) if(segt[j*2]<segt[j*2+1]) j=j*2; else j=j*2+1;
int cur = j&~(1<<7);
int curcost = segt[j];
segt[j] = FIN;
for(; j > 1; j>>=1) segt[j>>1] = min(segt[j],segt[j^1]);
if(cur == q) {
printf("%d\n", curcost);
break;
}
for(int i = 0; i < (int)graph[cur].size(); i++) {
int to = graph[cur][i].first;
int ecost = graph[cur][i].second.first;
if(r==1) ecost = graph[cur][i].second.second;
if(segt[to+(1<<7)] != FIN && segt[to+(1<<7)] > curcost+ecost) {
segt[to+(1<<7)] = curcost+ecost;
for(j = to+(1<<7); j > 1; j>>=1) segt[j>>1] = min(segt[j],segt[j^1]);
}
}
}
}
}
return 0;
}
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