#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=0; //←kの初期化を追加
    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(sizeof(int*)*a);
    if(mat == NULL){
    	printf("ERROR\n");
    	return 0;
    }
 
    for(i=0; i<a; i++){
    	mat[i] = (int*)malloc(sizeof(int)*b);
    	if(mat[i] == NULL){
    		printf("ERROR\n");
    		return 0;
    	}
    }
 
 
 
	//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;
			k += 1;
		}
	}
 
    //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？
    for(i=0; i<a; i++){
    	free(mat[i]);
    }
    free(mat);
 
 
    return 0;
}
 

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