我有一份我一直在做的工作。我的代码似乎具有正确的数学运算和正确的顺序（至少顺序），但我的答案有点棘手。我根据输入值得到了每个问题的一部分，但输入值从未与输入值相同。有什么关于我缺少的C操作顺序导致这个吗？
我觉得问题出在
intPeople = intCarCounter * intTrainCounter * CAR_CAPACITY;
对于样本运行＃3，前两个输入我得到120个人（比正确的答案正好多20个），剩余数字是样本运行＃4中的内容。在第三个输入上，我得到了112个人，这也是样本＃4的正确答案。最后，在样本运行＃4上，我得到128个人（比正确答案多16个），剩余数量应该是样本运行＃3中的数字。有什么想法吗？
分配： http://cop3223.blogspot.com/2013/01/problem-c-roller-coaster-design-coasterc.html
我的代码：
#include <stdio.h>
#include <stdlib.h>
#define FIRST_CAR_LENGTH 10
#define NORMAL_CAR_LENGTH 8
#define CAR_CAPACITY 4
int main(void)
{
/* Initialize Variables */
int intTrack,intMaxTrainSize,intActualTrainSize,intPeople,intCarCounter,intTrainCounter,n;
/* Ask user for value of N */
printf("What is the value for N?> ");
scanf("%d",&n);
for (int i=0; i<n;i++)
{
/* Ask user for total length of track */
printf("\nWhat is the total length of the track, in feet?> ");
scanf("%d",&intTrack);
/* Ask user for maximum length of each train */
printf("What is the maximum length of a train, in feet?> ");
scanf("%d",&intMaxTrainSize);
/* Set/Reset initial values of intActualTrainSize, intCarCounter and intTrainCounter */
/* Each train will begin with FIRST_CAR_LENGTH -> intActualTrainSize=FIRST_CAR_LENGTH */
/* Each train will begin with 1 car -> intCarCounter=1 */
/* Train counter will begin at 0 -> intTrainCounter=0 */
intActualTrainSize=FIRST_CAR_LENGTH;
intCarCounter=1;
intTrainCounter=0;
/* Continue to add additional cars using NORMAL_CAR_LENGTH until the maximum train size has been reached */
/* Count how many NORMAL_CAR_LENGTH cars are added -> intCarCounter++*/
while (intActualTrainSize < intMaxTrainSize)
{
intActualTrainSize=intActualTrainSize+NORMAL_CAR_LENGTH;
intCarCounter++;
}
/* Count how many trains can be added until 25% of the track is used up -> intTrainCounter++ */
while (intTrainCounter*intActualTrainSize < (int)(intTrack*.25))
{
intTrainCounter++;
}
/* Count how many people can be on the track at one time -> intPeople = intCarCounter * intTrainCounter * CAR_CAPACITY */
intPeople = intCarCounter * intTrainCounter * CAR_CAPACITY;
printf("\nYour ride can have at most %d people on it at one time.",intPeople);
if (intActualTrainSize>intMaxTrainSize)
printf("\nMaximum Train Length has surplus of %d feet.\n",intActualTrainSize-intMaxTrainSize);
else if (intMaxTrainSize==intActualTrainSize)
printf("\nMaximum Length fits exactly.\n");
}
system("pause");
return 0;
}
答案 0 :(得分：2)
您使用循环来计算列车计数器和汽车计数器，相反，您可以使用整数运算来计算这些值。我附上了我的解决方案，不涉及循环。它使调试更容易。我提供两个版本。版本1 sassumes整数除法不圆整。版本2更安全，因为它在分割之前减去剩余部分。
//VERSION 1:
#include <stdio.h>
#define FIRST_CAR_LENGTH 10
#define NORMAL_CAR_LENGTH 8
#define CAR_CAPACITY 4
int main(void)
{
int N, i;
int trackSize;
int trainSize;
int numberPeople;
int numberCars;
int trainsPerTrack;
int surplus;
printf("What is the value for N?");
scanf("%d", &N);
for(i=0; i < N; i++)
{
printf("What is the total length of the track, in feet?\n");
scanf("%d", &trackSize);
printf("What is the maximum length of a train, in feet?\n");
scanf("%d", &trainSize);
trainsPerTrack = trackSize / (4 * trainSize);
numberCars = (trainSize -FIRST_CAR_LENGTH) / NORMAL_CAR_LENGTH + 1;
numberPeople = trainsPerTrack * numberCars * CAR_CAPACITY;
printf("Your ride can have at most %d people on it at one time.\n", numberPeople);
surplus = (trainSize - FIRST_CAR_LENGTH) % NORMAL_CAR_LENGTH;
if(surplus)
printf("Maximum Train Length has surplus of %d feet\n\n", surplus);
else
printf("Maximum Length fits exactly\n\n");
}
return 0;
}
VERSION 2:
#include <stdio.h>
#define FIRST_CAR_LENGTH 10
#define NORMAL_CAR_LENGTH 8
#define CAR_CAPACITY 4
int main(void)
{
int N, i;
int trackSize;
int trainSize;
int numberPeople;
int numberCars;
int trainsPerTrack;
int surplus;
printf("What is the value for N?");
scanf("%d", &N);
for(i=0; i < N; i++)
{
printf("What is the total length of the track, in feet?\n");
scanf("%d", &trackSize);
printf("What is the maximum length of a train, in feet?\n");
scanf("%d", &trainSize);
trainsPerTrack = (trackSize- (trackSize % (4*trainSize))) / (4 * trainSize);
int forSmallerCars = trainSize - FIRST_CAR_LENGTH;
numberCars = (forSmallerCars - (forSmallerCars % NORMAL_CAR_LENGTH)) / NORMAL_CAR_LENGTH + 1;
numberPeople = trainsPerTrack * numberCars * CAR_CAPACITY;
printf("Your ride can have at most %d people on it at one time.\n", numberPeople);
surplus = (trainSize - FIRST_CAR_LENGTH) % NORMAL_CAR_LENGTH;
if(surplus)
printf("Maximum Train Length has surplus of %d feet\n\n", surplus);
else
printf("Maximum Length fits exactly\n\n");
}
return 0;
}
答案 1 :(得分：1)
不确定它是否有直接贡献，但您需要重新检查以下
while (intActualTrainSize +NORMAL_CAR_LENGTH <= intMaxTrainSize )
{ ^^^^^^^^^^^^^^^^^^
intActualTrainSize=intActualTrainSize+NORMAL_CAR_LENGTH;
intCarCounter++;
}
您的代码允许实际列车大小超出最大列车大小，因此可能是额外20的10。此检查将确保您只添加车辆，如果它仍然保持在最大值。
与列车计数器类似，也可能会溢出。
尝试将此类while循环转换为数学公式，如果可以的话，更高效，更易读。
答案 2 :(得分：0)
你的火车在说明
的路线上结束的时间太长了 while (intActualTrainSize < intMaxTrainSize)
{
intActualTrainSize=intActualTrainSize+NORMAL_CAR_LENGTH;
intCarCounter++;
}
因为你将执行这个循环，直到火车太长......
答案 3 :(得分：0)
不建议输入变量名称和一个字符变量名称。使用固定值递增循环中的计数器随乘法一起提供，不需要迭代。在循环的最后一次迭代中，实际列车大小超过最大值。如果用户提供的最大列车大小低于FIRST_CAR_LENGTH怎么办？首先计算实际列车尺寸的方法是正确的。如果存在盈余，哈桑的答案似乎是错误的。
const double occ = 0.25;
int track;
int max_train;
int cap;
int num_car;
int num_train = 0;
int train = 0;
printf( "Length of track? "); scanf( "%d", &track );
printf( "Max length of train? "); scanf( "%d", &max_train );
num_car = std::max( 0, max_train - FIRST_CAR_LENGTH + NORMAL_CAR_LENGTH ) / NORMAL_CAR_LENGTH;
if( 0 < num_car )
{
train = FIRST_CAR_LENGTH + NORMAL_CAR_LENGTH * ( num_car - 1 );
num_train = ( int ) ( occ * track ) / train;
}
cap = CAR_CAPACITY * num_car * num_train;
printf( "Capacity: %d; Train surplus: %d\n", cap, max_train - train );