#include <stdio.h>
 
void cat_data(int *data1,const int *data2,int len2);
 
int main(void) {
 
	int data1[7] = {1,2};
	int data2[5] = {3,4,5,6,7};
	int size = sizeof(data2)/sizeof(data2[0]);
 
	cat_data(data1,data2,size);
 
	for(int i=0;i<7;i++){
 
		printf("data1[%d]=%d\n",i,data1[i]);
 
	}
 
	return 0;
}
 
void cat_data(int *data1,const int *data2,int len2){
 
	int len1 = sizeof(data1)/sizeof(data1[0]);
 
	for(int i=0;i<len2;i++){
 
		data1[i+(len1-len2)] = data2[i];
 
	}
}

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