下列Dijkstra算法中，横线处应该填入的是（    ）。

#include <iostream>

using namespace std;

#define N 100

int n, e, s;

const int inf = 0x7fffff;

int dis[N + 1];

int cheak[N + 1];

int graph[N + 1][N + 1];

int main() {

for (int i = 1; i <= N; i++)

dis[i] = inf;

cin >> n >> e;

for (int i = 1; i <= e; i++) {

int a, b, c;

cin >> a >> b >> c;

graph[a][b] = c;

}

cin >> s;

dis[s] = 0;

for (int i = 1; i <= n; i++) {

int minn = inf, minx;

for (int j = 1; j <= n; j++) {

if (__________) {

// 在此处填入选项

minn = dis[j];

minx = j;

}

}

cheak[minx] = 1;

for (int j = 1; j <= n; j++) {

if (graph[minx][j] > 0) {

if (minn + graph[minx][j] < dis[j]) {

dis[j] = minn + graph[minx][j];

}

}

}

}

}