#include <stdio.h>
#include <stdlib.h>
 
//必要があれば変数などを追加してもOKです
 
int main(){
    int i,j,k;
    int a,b;
    int **mat;
    scanf("%d %d",&a,&b);
 
	//ここで2次元配列の動的確保をする
 
    mat = (int**)malloc(4*a);
    for (i = 0; i < a; i++){
      mat[i] = (int*)malloc(sizeof(int)*b);
    }
 
 
	//ここで2次元配列に数値を代入する
    for(i=0;i<a;i++){
      for(j=0;j<b;j++){
        mat[i][j] = k++;
      }
    }
 
 
    //以下の部分は表示の部分です
    //いじらなくてOK
    for(i=0;i<a;i++){
        for(j=0;j<b;j++){
            printf("%d ",mat[i][j]);
        }
        printf("\n");
    }
 
    //さて，最後に忘れずにすることと言えば？
    if(mat == NULL){
      printf("ERROR\n");
    }
 
 
    return 0;
}
 

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