Question

我正在为计算机科学任务。我们必须制定击球平均计划。我有它的工作，它将计算击中，出局，单打等，但当涉及到计算击球率时，它会提高0.000。我不知道为什么，我做了大量的谷歌搜索，尝试使变量双和浮动等，这里是代码：

#include <iostream>
#include <iomanip>
#include <cstdlib>

using namespace std;

int main(){
const int MAX_TIMES_AT_BAT = 1000;
int hits = 0, timesBatted = 0, outs = 0, walks = 0, singles = 0, doubles = 0, triples = 0, homeRuns = 0;
float battingAverage = 0.0, sluggingPercentage = 0.0;

for(int i = 0; i < MAX_TIMES_AT_BAT; i++){
    int random = rand() % 100 +1;

    if(random > 0 && random <= 35){ 
        outs++;
    }else if(random > 35 && random <= 51){
        walks++;
    }else if(random > 51 && random <= 71){
        singles++;
        hits++;
    }else if(random > 71 && random <= 86){
        doubles++;
        hits++;
    }else if(random > 86 && random <= 95){
        triples++;
        hits++;
    }else if(random > 95 && random <= 100){
        homeRuns++;
        hits++;
    }else{
        cout << "ERROR WITH TESTING RANDOM!!!";
        return(0);
    }
    timesBatted++;
}
    cout << timesBatted << " " << hits << " " << outs << " " << walks << " " << singles << " " << doubles << " " << triples << " " << homeRuns << endl;


battingAverage = (hits / (timesBatted - walks));
sluggingPercentage = (singles + doubles * 2 + triples * 3 + homeRuns*4) / (timesBatted - walks);

cout << fixed << setprecision(3) << "Batting Average: " << battingAverage << "\nSlugging Percentage: " << sluggingPercentage << endl;


return 0;
}

任何帮助都会很棒！怎么了？我计算了它，击球率应该是0.5646，击球率应该是1.0937。它的显示是0.0000和1.0000。在此先感谢!!!

Answer 1

您正在执行整数除法。将至少一个操作数显式地转换为double。例如：

battingAverage = (static_cast<float>(hits) / (timesBatted - walks));

sluggingPercentage的作业相同。

Answer 2

简单地将int除以int是另一个int。只需将其中一个投放到double。

例如，

battingAverage = static_cast<double>(hits) / (timesBatted - walks)
sluggingPercentage = static_cast<double>(singles + doubles * 2 + triples * 3 + homeRuns*4) / (timesBatted - walks)

始终使用C ++强制转换（static_cast<double>()）而不是C强制转换(double)()，因为编译器会为您提供有关何时出错的更多提示。

PS不要讨厌C ++！ :(显示它有点爱，它会爱你回来！

分裂和cout的C ++问题

2 个答案: