【leetcode】彙總區間

 

char ** summaryRanges(int* nums, int numsSize, int* returnSize){
    char** res=malloc(numsSize*sizeof(char*));
    *returnSize=0;
    int p=0,q=0;
    while(q<numsSize){
        while(q+1<numsSize && nums[q]+1==nums[q+1]) ++q;
        res[*returnSize]=malloc(100*sizeof(char));//數字個數是q-p+1個,可是轉換成字符串可能佔不少位,好比一個數字1000000就佔7個字符位
        if(q==p){
            sprintf(res[*returnSize],"%d",nums[q]);//sprintf發送格式化輸出到字符串
        }
        else{
            sprintf(res[*returnSize],"%d->%d",nums[p],nums[q]);
        }
        ++(*returnSize);
        ++q;
        p=q;
    }

    return res;
}