【leetcode】矩阵中的幸运数

int* luckyNumbers (int** matrix, int matrixSize, int* matrixColSize, int* returnSize){
    int i,j,k,count=0,min,col,pst=0;
    int* retArr = (int*)malloc(sizeof(int));
    for (i=0; i<matrixSize; i++)
    {
        min = 100001;
        for (j=0; j<matrixColSize[i]; j++)
        {
            if (matrix[i][j] < min) 
            {
                min = matrix[i][j];
                col = j;
            }
        }        
        for (k=0; k<matrixSize; k++)
        {
            if (k == i) continue;
            if (matrix[k][col] > min) break;
        }
        if (k == matrixSize) retArr[pst++]=min;;
    }
    *returnSize=pst;
    return retArr;
}