simple and neat

```
result=triangle
for i in range(1,len(triangle)):
for j in range(1,len(triangle[i])-1):
result[i][j]+=min(result[i-1][j-1],result[i-1][j])
result[i][0]+=result[i-1][0]
result[i][i]+=result[i-1][i-1]
return min(result[len(triangle)-1])
```