// array.c
#include <stdio.h>
 
int main(void)
{
    int array1[3];  // 初期値不明
    int array2[] = { 1, 2, 3 };  // 配列の宣言時のみ初期値を指定できる
    int array3[3] = { 1, 2 };  // 3つ目の要素には初期値が無いが自動で0が代入される
    array1[0] = 1;
    array1[1] = 2;
    array1[2] = 3;
 
    for(int i=0;i<sizeof(array1)/sizeof(int);++i){
        printf("array1[%d]: %d\n",i,array1[i]);  // array1と2は1,2,3の順番で出力される
        printf("array2[%d]: %d\n",i,array2[i]); 
        printf("array3[%d]: %d\n\n",i,array3[i]); // array3は1,2,0の順番で出力される
    }
    return 0;
}

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