#include<stdio.h>
struct edge{
int st,en,len;
};
edge data[1005];
long double t[2][35],p[2][35];
long double cnt[35];
int n,m;
int main()
{
freopen("input.txt","r",stdin);
long double ans=0;
int s=0, e=1, ct=0;
scanf("%d%d",&n,&m);
for(int i=0;i<m;i++){
scanf("%d%d%d",&data[i].st,&data[i].en,&data[i].len);
cnt[data[i].st]++;
}
p[s][0]=1;
while(1){
int i;
for(i=0;i<n;i++){
if(p[s][i]>1e-30||t[s][i]>1e-30)break;
}
if(i==n)break;
for(int i=0;i<=n;i++)p[e][i]=t[e][i]=0;
for(int i=0;i<m;i++){
p[e][data[i].en]+=p[s][data[i].st]/cnt[data[i].st];
t[e][data[i].en]+=(t[s][data[i].st]+data[i].len*p[s][data[i].st])/cnt[data[i].st];
}
ans+=t[e][n];
s=!s; e=!e;
}
printf("%.9lf",ans);
}
/*
#include<stdlib.h>
int main()
{
freopen("input.txt","w",stdout);
for(int i=0;i<1000;i++){
printf("%d %d 50\n",rand()%30,rand()%30);
}
}*/
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
0 ms |
1092 KB |
open (syscall #2) was called by the program (disallowed syscall) |
2 |
Halted |
0 ms |
0 KB |
- |