ACM刷题之路（九）数论-逆序组 交换座位

#include<stdio.h>
#include<string.h>
#include<iostream>
using namespace std;

char a[9];
bool b[9];
int geshu;
void dfs(int x){
    b[x] = true;
    geshu++;
    if (b[a[x] - '0'] == false)
        dfs(a[x] - '0');
}

int main(){
    while (gets(a + 1)){
        int sum = 0, i, sum2 = 0;
        memset(b, false, sizeof(b));
        for (i = 1; i <= 8; i++){
            geshu = 0;
            if (b[i] == false){
                geshu = 0;
                dfs(i);
            }
            if (geshu > 1){
                sum += geshu - 1;
            }
        }
        cout << sum << endl;
    }
    return 0;
}