题解 | 单组_二维数组

#include <iostream>
#include<vector>
using namespace std;
#define ll long long
int main() {
    ll n,m,sum=0;
    cin>>n>>m;
    vector<vector<ll>>a(n,vector<ll>(m));
    for(int i=0;i<n;i++){
        for(int j=0;j<m;j++){
            cin>>a[i][j];
            sum+=a[i][j];
        }
    }
    cout<<sum<<endl;
}