#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 len2 = sizeof(data2) / sizeof(data2[0]);
    cat_data(data1, data2, len2);
    for (int i = 0; i < len2 + 2; i++) {
        printf("cat_data[%d] = %d\n", i, data1[i]); 
    }
    return 0;
}
 
void cat_data(int *data1, const int *data2, int len2){
    for (int i = 0; i < len2; i++) {    
        data1[i + 2] = data2[i];        
    }
}
 

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