Simple FEM Solver

sample input

* NODES 
10 0 0
20 1 0
30 2 0
40 1 1
50 2 1
60 1 2

* ELEMS
100 10 20
200 20 30
300 10 40
400 20 40
500 20 50
600 30 50
700 40 50
800 40 60
900 50 60

converted json input

{
    "nodes": {
        10: [0, 0],
        20: [1, 0],
        30: [2, 0],
        40: [1, 1],
        50: [2, 1],
        60: [1, 2],
    },
    "links": {
        100: [10, 20],
        200: [20, 30],
        300: [10, 40],
        400: [20, 40],
        500: [20, 50],
        600: [30, 50],
        700: [40, 50],
        800: [40, 60],
        900: [50, 60],
    },
}