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

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