题解 | #单组_二维数组#

#include <iostream>
using namespace std;
using ll=long long;
const int N=1010;
int a[N][N];
int main(void)
{
	ios::sync_with_stdio(false);
	cin.tie(0);
	ll sum=0;
	int n,m,i,j;
	cin>>n>>m;
	for(i=1;i<=n;++i)
		for(j=1;j<=m;++j)
			cin>>a[i][j];
	for(i=1;i<=n;++i)
		for(j=1;j<=m;++j)
			sum+=a[i][j];
	cout<<sum;
	return 0;
}

import java.util.Scanner;
public class Main{
    public static void main(String[] args){
        Scanner sc=new Scanner(System.in);
        long sum=0;
        int n,m,i,j;
        n=sc.nextInt();
        m=sc.nextInt();
        int[][] a=new int[n+5][m+5];
        for(i=1;i<=n;++i)
            for(j=1;j<=m;++j)
                a[i][j]=sc.nextInt();
        for(i=1;i<=n;++i)
            for(j=1;j<=m;++j)
                sum+=a[i][j];
        System.out.print(sum);
    }
}

n,m=map(int,input().split())
a=[list(map(int,input().split())) for i in range(0,n)]
s=0
for i in a:
    # s+=sum(i)
    for j in i:
        s+=j
print(s)