#include <stdio.h>
 
void cat_data(int *data1,const int *data2,int len1,int len2);
 
int main(void) {
	int d1[7]={1,2};
	int d2[5]={3,4,5,6,7};
	int l1=sizeof(d1)/sizeof(d1[0]);//l1はd1の要素数。ここでは7
	int l2=sizeof(d2)/sizeof(d2[0]);//l2はd2の要素数。ここでは5
	cat_data(d1,d2,l1,l2);
	for(int i=0;i<7;i++){
		printf("data1[%d]=%d\n",i,d1[i]);
	}
	return 0;
}
 
void cat_data(int *data1,const int *data2,int len1,int len2){//*data1==data1[]==d1[0]
	for(int i=0;i<len2;i++){
		data1[(len1-len2)+i]=data2[i];//d1とd2の要素数の差が正であるならばなんでも対応できるように
	}
}

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