#include <iostream>
#include <cstring>
using namespace std;
int n,m,a[251][251],d[251][251],ans,x,y;
int main()
{
scanf("%d%d",&n,&m);
for (int i=1;i<=n;i++)
for (int j=1;j<=n;j++)
{
a[i][j]=20000000;
d[i][j]=20000000;
}
ans=20000000;
for (int i=1;i<=m;i++)
{
scanf("%d%d",&x,&y);
scanf("%d",&d[x][y]);
d[y][x]=d[x][y];
a[x][y]=d[x][y];
a[y][x]=d[x][y];
}
for (int k=1;k<=n;k++)
{
for (int i=1;i<k;i++)
for (int j=i+1;j<k;j++)
{
if (ans>a[i][j]+d[i][k]+d[k][j]) ans=a[i][j]+d[i][k]+d[k][j];
}
for (int i=1;i<=n;i++)
for (int j=1;j<=n;j++)
{
if(a[i][k]+a[k][j]<a[i][j])
a[i][j]=a[i][k]+a[k][j];
}
}
if (ans==20000000) printf("He will never come back.");
else printf("%d",ans);
}
ac100
#include <cstdio>
#include <iostream>
#include <cstring>
using namespace std;
int n,m,a[251][251],d[251][251],ans,x,y;
int main()
{
scanf("%d%d",&n,&m);
for (int i=1;i<=n;i++)
for (int j=1;j<=n;j++)
{
a[i][j]=20000000;
d[i][j]=20000000;
}
ans=20000000;
for (int i=1;i<=m;i++)
{
scanf("%d%d",&x,&y);
scanf("%d",&d[x][y]);
d[y][x]=d[x][y];
a[x][y]=d[x][y];
a[y][x]=d[x][y];
}
for (int k=1;k<=n;k++)
for (int i=1;i<=n;i++)
for (int j=1;j<=n;j++)
{
if(a[i][k]+a[k][j]<a[i][j])
a[i][j]=a[i][k]+a[k][j];
}
for (int k=1;k<=n;k++)
for (int i=1;i<k;i++)
for (int j=i+1;j<k;j++)
{
if (ans>a[i][j]+d[i][k]+d[k][j]) ans=a[i][j]+d[i][k]+d[k][j];
}
if (ans==20000000) printf("He will never come back.");
else printf("%d",ans);
}
wa30
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