diff options
Diffstat (limited to 'online_stock_span.c')
-rw-r--r-- | online_stock_span.c | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/online_stock_span.c b/online_stock_span.c new file mode 100644 index 0000000..bfa3895 --- /dev/null +++ b/online_stock_span.c @@ -0,0 +1,85 @@ +// 901. Online Stock Span +#include "leetcode.h" + +/* + * design an algorithm that collects daily price quotes for some stock and + * returns the span of that stock's price for the current day. the span of the + * stock's price in one day is the maximum number of consecutive days (starting + * from that day and going backward) for which the stock price was less than or + * equal to the price of that day. if the prices of the stock in the last four + * days is '[7,34,1,2]' and the price of the stock today is 8, then the span of + * today is 3 because starting from today, the price of the stock was less than + * or equal 8 for 3 consecutive days. + */ + +typedef struct { + int first; + int second; +} pair; + +typedef struct { + pair data; + struct node *next; +} node; + +typedef struct { + node *top; +} StockSpanner; + +node *create_node(pair data) { + node *new = (node *)malloc(sizeof(node)); + new->data = data; + new->next = NULL; + return new; +} + +StockSpanner *stockSpannerCreate() { + StockSpanner *obj = (StockSpanner *)malloc(sizeof(StockSpanner)); + obj->top = NULL; + return obj; +} + +void push(StockSpanner *obj, pair data) { + node *curr = create_node(data); + curr->next = obj->top; + obj->top = curr; +} + +pair pop(StockSpanner *obj) { + if (obj->top == NULL) { + pair empty = {0, 0}; + return empty; + } + node *tmp = obj->top; + pair data = tmp->data; + obj->top = tmp->next; + free(tmp); + return data; +} + +int stockSpannerNext(StockSpanner *obj, int price) { + int cnt = 1; + while (obj->top && obj->top->data.first <= price) { + cnt += obj->top->data.second; + pop(obj); + } + push(obj, (pair){price, cnt}); + return cnt; +} + +void stockSpannerFree(StockSpanner *obj) { + while (obj->top) + pop(obj); + free(obj); +} + +int main() { + StockSpanner *obj = stockSpannerCreate(); + printf("%d\n", stockSpannerNext(obj, 100)); // expect: 1 + printf("%d\n", stockSpannerNext(obj, 80)); // expect: 1 + printf("%d\n", stockSpannerNext(obj, 60)); // expect: 1 + printf("%d\n", stockSpannerNext(obj, 70)); // expect: 2 + printf("%d\n", stockSpannerNext(obj, 60)); // expect: 1 + printf("%d\n", stockSpannerNext(obj, 75)); // expect: 4 + printf("%d\n", stockSpannerNext(obj, 85)); // expect: 6 +} |