数组重塑

public int[][] matrixReshape(int[][] nums, int r, int c) {
    if(nums.length==0)
        return nums;
    int oR = nums.length , oC = nums[0].length;
    if(oR*oC!=r*c)
        return nums;
    int[][] result = new int[r][c];
    int count=0;
    for(int i=0;i<r;i++)
        for(int j=0;j<c;j++){
            result[i][j]=nums[count/oC][count%oC];
            count++;
        }
    return result;
}