40. 组合总和 IIc

/**
 * Return an array of arrays of size *returnSize.
 * The sizes of the arrays are returned as *returnColumnSizes array.
 * Note: Both returned array and *columnSizes array must be malloced, assume caller calls free().
 */
 int temp[100];
 int cmp(const void* a,const void* b){
    return *(int*)a-*(int*)b;
 }

void dfs(int** array,int* candidates,int candidatesSize,int target,int* returnSize,int* column,int index,int sum,int count){
    if(sum>target||index>candidatesSize) return;
    if(index==candidatesSize&&sum!=target) return;
    if(sum==target){
        column[*returnSize]=count;
        array[*returnSize]=(int*)malloc(sizeof(int)*count);
        for(int i=0;i<count;i++) array[*returnSize][i]=temp[i];
        (*returnSize)++;
        return;
    }
    int use[51]={0};
    for(int i=index;i<candidatesSize;i++){
        if(use[candidates[i]]!=0) continue;
        temp[count]=candidates[i];
        use[candidates[i]]=1;
        dfs(array,candidates,candidatesSize,target,returnSize,column,i+1,sum+candidates[i],count+1);
    }
}

int** combinationSum2(int* candidates, int candidatesSize, int target, int* returnSize, int** returnColumnSizes) {
    *returnSize=0;
    int** array=(int**)malloc(sizeof(int*)*2000);
    int* column=(int*)malloc(sizeof(int)*2000);
    qsort(candidates,candidatesSize,sizeof(int),cmp);
    dfs(array,candidates,candidatesSize,target,returnSize,column,0,0,0);
    *returnColumnSizes=column;
    return  array;
}