public static double sumMatrix(int [][] m){
double sum = 0;
for (int i = 0; i < m.length; i++) {
for (int j = 0; j < m[i].length; j++) {
sum += m[i][j];
}
}
return sum;
}
就這樣就行了 測試方法如下：
public static void main(String[] args) {
int[][] m = {{1,2},{3,4,5},{6,7},{8,9,10}};
double sum = sumMatrix(m);
System.out.println(sum);
}