1148: combine one of three digits

1148: Combine one of the three digits

Title Description
hold 1、2、3、4、5、6、7、8、9 Combine into 3 individual 3 digit , Each number is required to be used only once , Make each 3 The number of digits is a complete square number . Output these three three digits in descending order .
Input
nothing
Output
Output these three three digits in descending order , Separated by spaces . Output takes up one line .
source / classification

#include<stdio.h>
#include<string.h>
#define N 20
/*  First find the three digit complete square number   Then find out what is not repeated in turn  */

// Judge whether there are duplicate numbers in two three digit numbers , No duplicate return 1
int Isrepeat(a,b){
    
    if(b%10==a%10||b%10==a/10%10||b%10==a/100) return 0;
    if(b/10%10==a%10||b/10%10==a/10%10||b/10%10==a/100) return 0;
    if(b/100==a%10||b/100==a/10%10||b/100==a/100) return 0;
    return 1;
}
int main(){
    
    int a[N],x,y=0,i,j,k;
    // Directly find the three digits that you don't repeat , Can narrow the scope （13-31）
    for(i=13;i<32;i++){
    
        x=i*i;
        if((x%10!=x/100)&&(x/100!=x/10%10)&&(x%10!=x/10%10)) a[y++]=x;
    }
    // The three-level loop finds three non repeating three digits , And in order 
    for(i=0;i<y-2;i++){
    
        for(j=i+1;j<y-1;j++){
    
            for(k=j+1;k<y;k++){
    
                if(Isrepeat(a[i],a[j])&&Isrepeat(a[j],a[k])&&Isrepeat(a[i],a[k]))
                    printf("%d %d %d\n",a[i],a[j],a[k]);
            }
        }
    }
    return 0;
}