int shortestPathLength(int[][] grid) {
if (grid == null || grid.length == 0) { return 0; }
int n = grid.length, m = grid[0].length;
int[][] cache = new int[n][m];
if (grid[0][0] != 0) { return 0; } else { cache[0][0] = 1; }
for (int i = 1; i < n; i++) {
cache[i][0] = (grid[i][0] != 1 && cache[i - 1][0] != 0) ? cache[i - 1][0] + 1 : 0;
}
for (int j = 1; j < m; j++) {
cache[0][j] = (grid[0][j] != 1 && cache[0][j - 1] != 0) ? cache[0][j - 1] + 1 : 0;
}
for (int i = 1; i < n; i++) {
for (int j = 1; j < m; j++) {
if (grid[i][j] != 1) {
if (cache[i - 1][j] == 0 && cache[i][j - 1] == 0) {
cache[i][j] = 0;
} else if (cache[i - 1][j] == 0 || cache[i][j - 1] == 0) {
cache[i][j] = cache[i - 1][j] + cache[i][j - 1] + 1;
} else {
cache[i][j] = Math.min(cache[i - 1][j], cache[i][j - 1]) + 1;
}
}
}
}
printArrayI(cache);
return cache[n - 1][m - 1];
}