#include <stdio.h>
 
void cat_data(int*data1,const int*data2,int len2);
 
int main(void) {
	int data1[7]={1,2,0,0,0,0,0};
	int data2[5]={3,4,5,6,7};
 
	int len2= sizeof(data2)/sizeof(data2[0]);  //全体のバイト数÷1つのバイト数=要素の数
 
	cat_data(data1, data2, len2);
 
	for (int k = 0; k < 7; k++) {
        printf("data1[%d] = %d\n", k, data1[k]);  //結果を出力
    }
 
 
	return 0;
}
 
void cat_data(int*data1,const int*data2,int len2){
	int i=0;
 
	while (*data1 != 0) {
        data1++;            //ポインタを数値が入っていない最初に持ってくる
    }
 
    while (len2 > 0) {
        *data1++ = *data2++;//1つずつ入れていく
        len2--;
    }
 
}

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