HDU 5095 Linearization of the kernel functions in SVM （坑水）

比较坑的水题，首项前面的符号，-1，+1，只有数字项的时候要输出0。

感受一下这些数据

16
0 0 0 0 0 0 0 0 0 -1
0 0 0 0 0 0 0 0 0 1
0 0 0 0 0 0 0 0 0 0
1 0 0 0 0 0 0 0 0 0
-1 0 0 0 0 0 0 0 0 0
-1 -1 -1 -41 -1 -1 -1 -1 -1 -1
-1 5 -2 0 0 0 0 0 0 0
1 1 1 1 1 1 1 1 1 1
-1 -1 -1 -1 -1 -1 -1 -1 -1 -1
0 0 0 0 0 -1 -1 -1 -1 -1
0 0 0 0 0 1 1 1 1 1
1 1 1 1 1 0 0 0 0 0
-1 -1 -1 -1 -1 0 0 0 0 0
1 1 1 1 1 1 1 1 1 0
0 46 3 4 -5 -22 -8 -32 24 27
2 31 -5 0 0 12 0 0 -49 12

#include<cstdio>
#include<cstring>
#include<cmath>
char *bin = "pqruvwxyz";
typedef int ll;

ll a[10];
int flag;
void dfs(int d)
{
    if(d == 9) {
        return;
    }
    if(a[d]){
        if(std::abs(a[d]) == 1){
            if(a[d]>0){
                if(flag) printf("+");
                printf("%c",bin[d]);
            }
            else printf("-%c",bin[d]);
        }
        else {
            if(a[d]>0){
                if(flag) printf("+");
                printf("%d%c",a[d],bin[d]);

            }else {
                printf("%d%c",a[d],bin[d]);
            }
        }
        flag = 1;

    }
    dfs(d+1);
}

int main()
{
    int n;
    scanf("%d",&n);
    while(n--){
       // memset(a,0,sizeof(a));
        for(int i = 0; i < 10; i++)
            scanf("%d",a+i);
        flag = 0;
        dfs(0);
        if(!flag){
            printf("%d",a[9]);
        }
        else {
            if(a[9]){
                if(a[9]>0)
                    printf("+%d",a[9]);
                else
                    printf("%d",a[9]);
            }
        }
        printf("\n");
    }
    return 0;
}