#include <stdio.h>
#include <stdlib.h>
 
//把答案往前傳 
int sum_1(int n){
    if(n == 0){
        return 0;
    }else{
        return n+sum_1(n-1);      
    }
}
 
//把答案往後傳 
void sum_2(int n,int ans2){
    if( n==0 ){
        printf("遞迴二  1+2+...+10=%d\n",ans2);
        return;         
    }else{
        sum_2(n-1,ans2+n);      
    }      
}
 
int main(int argc, char *argv[])
{
 
    int ans1 =sum_1(10);
    printf("遞迴一  1+2+...+10=%d\n",ans1);
 
    sum_2(10,0);
    system("PAUSE");	
    return 0;
}
 

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