有点怕double的误差。。。其实判断的时猴条件不用0.5邕0.495就好

#include <iostream>
#include <stdio.h>
#include <vector>
#include <string>
using namespace std;

const double MAXDIST = 10000000.0;

int main() {
	int N, M, K;
	cin >> N >> M >> K;
	double dirDist[32][32];
	for(int i = 0; i < N; i++){
		for(int j = 0; j < N; j++){
			if(i == j) dirDist[i][j] = 0;
			else dirDist[i][j] = MAXDIST;
		}
	}
	for(int i = 0; i < M; i++){
		int i1, i2;
		cin >> i1 >> i2;
		double rs;
		cin >> rs;

			dirDist[i1][i2] = rs;
			dirDist[i2][i1] = rs;

	}
	//cout << dirDist[0][1] << endl;
	string cityName[32];
	//bool isCity[32] = {0};
	int cityList[32];
	//int cityNum = 0;

	for(int i = 0; i < K; i++){
		int no;
		cin >> no;
		cin >> cityName[no];
		//isCity[no] = 1;
		cityList[i] = no;
		//cityNum ++;
	}

	//开始floyd
	double dist[2][32][32];
	int prev[2][32][32];
	for(int i = 0; i < N; i++){
		for(int j = 0; j < N; j++){
			if(i == j){
				prev[0][i][j] = i;
				dist[0][i][j] = 0;
				continue;
			}
			else{
				dist[0][i][j] = dirDist[i][j];
				if(dirDist[i][j]<MAXDIST-1) prev[0][i][j] = i;
				else prev[0][i][j] = -1;
			}
		}
	}

	for(int i = 0; i < N; i++){
		int from = i%2, to = (i+1)%2;
		for(int j = 0; j < N; j++){
			for(int k = 0; k < N; k++){
				if(i == j || i == k){
					dist[to][j][k] = dist[from][j][k];
					prev[to][j][k] = prev[from][j][k];
					continue;
				}
				if(j == k){
					dist[to][j][k] = 0;
					prev[to][j][k] = j;
				}
				else{
					dist[to][j][k] = dist[from][j][k];
					prev[to][j][k] = prev[from][j][k];
					double tempDist = dist[from][j][i] + dist[from][i][k];
					if(tempDist < dist[to][j][k]){
						dist[to][j][k] = tempDist;
						prev[to][j][k] = prev[from][i][k];
					}
				}
			}
		}
	}

	int resZu = N%2;

	int inq;
	cin >> inq;
	for(int ii = 0; ii < inq; ii++){
		int i1, i2;
		double dis;
		//char fei, sf, bf;
		cin >> i1 >> i2 >> dis;
		//int dis = zsd * 100 + (sf-'0') * 10 + (bf-'0');
		vector<int> cityIdx;
		vector<int> cityDist;
		for(int i = 0; i < K; i++){
			int idx = cityList[i];
			bool keyi = false;
			int idx1 = i1;
			while(idx1 != idx){
				idx1 = prev[resZu][idx][idx1];
				if(idx1 == -1) break;
				if(idx1 == i2){
					keyi = true;
					break;
				}
			}
			if(!keyi) continue;
			cityIdx.push_back(idx);
			double Dis = dist[resZu][idx][i1] - dis;
			int cityDis;
			int intDis = (int) Dis;
			if(Dis - intDis < 0.495) cityDis = intDis;
			else cityDis = intDis+1;
			cityDist.push_back(cityDis);
		}
		int sz = cityIdx.size();
		for(int i = 1; i < sz; i++){
			for(int j = i; j > 0; j--){
				if(cityDist[j] > cityDist[j-1] || (cityDist[j] == cityDist[j-1] && cityName[cityIdx[j]] > cityName[cityIdx[j-1]])){
					break;
				}
				int temp = cityDist[j];
				cityDist[j] = cityDist[j-1];
				cityDist[j-1] = temp;
				temp = cityIdx[j];
				cityIdx[j] = cityIdx[j-1];
				cityIdx[j-1] = temp;
			}
		}
		for(int i = 0; i < sz; i++){
			cout << cityName[cityIdx[i]];
			int lenn = cityName[cityIdx[i]].length();
			for(int j = 0; j < 20-lenn; j ++) cout << " ";
			cout << cityDist[i] << endl;
		}
		cout << endl;
	}

	return 0;
}