#include <stdio.h>

void cat_data(int *data1, const int *data2, int len2);

int main(void) {
	int i;
	int data1[7]={1,2};
	int data2[5]={3,4,5,6,7};
	int len1=sizeof(data1)/sizeof(data1[0]);
	int len2=sizeof(data2)/sizeof(data2[0]);
	cat_data(data1,data2,len1);
	for(i=0;i<len1;i++){
		printf("data[%d]=%d\n",i,data1[i]);
	}
	return 0;
}

void cat_data(int *data1, const int *data2, int len2){
	int i;
	int *p=data1+2;
	for(i=0;i<len2;i++){
		p[i]=data2[i];
	}
}