Most Profit from Stock Prices, One Transaction

@interface Solution: NSObject
-(int)mostProfitFromStockPrices:(NSArray<NSNumber *> *)prices;
@end

@implementation Solution
-(int)mostProfitFromStockPrices:(NSArray<NSNumber *> *)prices {
    if(prices.count < 2) return 0;
    int lowestSoFar = prices[0].intValue;
    int best = 0;
    for(int i = 1; i < prices.count; i++) {
        int profitHere = prices[i].intValue - lowestSoFar;
        best = MAX(best, profitHere);
        lowestSoFar = MIN(lowestSoFar, prices[i].intValue);
    }

    return best;
}
@end