POJ2718(穷举，贪心)

参考地址

一开始连题意都没搞懂就开始直接做，too young。应该静下来用5分钟分析，by the way, may be the typical usage of brute-force is “void” function instead of function with return value.

//#define LOCAL

#include <cstdio>
#include <cstring>
#include <string>
#include <cmath>
#include <ctype.h>
#include <algorithm>
#define SIZE 10

using namespace std;

int map[SIZE];

int brute(int size){
    if(size == 1)
        return map[0];
    else if(size == 2)
        return abs(map[0] - map[1]);

    int ans = -1;
    int mid = size / 2;

    do{
        if(map[0] != 0 && map[mid] != 0){
            int x = 0;
            int y = 0;

            for(int i = 0; i < mid; i++)
                x = x * 10 + map[i];
            for(int i = mid; i < size; i++)
                y = y * 10 + map[i];

            if(ans == -1 || ans > abs(x - y))
                ans = abs(x - y);

            /*for(int i = 0; i < size; i++)
                printf("%d ", map[i]);
            printf("\n");
            printf("x:%d y:%d\n", x, y);*/
        }
    }while(next_permutation(map, map + size));

    return ans;
}

int main(){
#ifdef LOCAL
    freopen("data.in", "r", stdin);
#endif
    int n;
    scanf("%d", &n);
    getchar();

    while(n--){
        int pos = 0;
        char c;
        while(scanf("%c", &c), c != '\n'){
            if(c != ' ')
                map[pos++] = c - '0';
        }

        /*for(int j = 0; j < pos; j++)
            printf("%d ", map[j]);
        printf("\n");*/
        //printf("%d", pos);

        printf("%d\n", brute(pos));
    }

    return 0;   
}