hdu3853LOOPS概率dp

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cmath>
#include <cstring>
using namespace std;
const int N=1005;
const double eps=1e-9;
int r,c;
double p1

,p2

,p3

,dp

;
int main()
{
while(scanf("%d%d",&r,&c)!=EOF){
memset(dp,0,sizeof(dp));
for(int i=0;i<r;i++)
for(int j=0;j<c;j++)
scanf("%lf%lf%lf",&p1[i][j],&p2[i][j],&p3[i][j]);
int j;
for(int i=r-1;i>=0;i--)//(i==r-1&&j==c-1)把这个放到这里====bug
for(j=c-1;j>=0;j--){
if((i==r-1&&j==c-1)||fabs(p1[i][j]-1.0)<eps) continue;
dp[i][j]=(dp[i][j+1]*p2[i][j]+dp[i+1][j]*p3[i][j]+2)/(1-p1[i][j]);
}
printf("%.3lf\n",dp[0][0]);
}
return 0;
}