USACO 2.4 Fractions to Decimals (模拟)

#include <stdio.h>
#define DEBUG 1
#define TESTCASES 9
#define MAX_DIGITS 100001

char decimal[MAX_DIGITS];
int lastRemainder[MAX_DIGITS];
char result[MAX_DIGITS];
int resultIndex;

int main(){
#if DEBUG
int testCase;
for (testCase = 1; testCase <= TESTCASES; testCase++){
char inputFileName[20] = "inputX.txt";
inputFileName[5] = '1' +  (testCase - 1);
freopen(inputFileName, "r", stdin);
printf("\n#%d\n", testCase);
#endif

int numerator, denominator;
scanf("%d%d", &numerator, &denominator);

int quotient = numerator / denominator;
char tempStr[1000000];
int len = 0;
do {
tempStr[len++] = quotient % 10 + '0';
quotient /= 10;
} while(quotient);
for (resultIndex = 0; resultIndex < len; resultIndex++)
result[resultIndex] = tempStr[len - 1 - resultIndex];

result[resultIndex++] = '.';

int digit;
for (digit = 0; digit < MAX_DIGITS; digit++)
lastRemainder[digit] = -1;

int remainder = numerator % denominator;
digit = 0;

int i;
while (1){
if (remainder == 0){
if (digit == 0)
result[resultIndex++] = '0';
else{
for (i = 0; i < digit; i++)
result[resultIndex++] = decimal[i];
}
break;
}

if (lastRemainder[remainder] != -1){
int repeatDigit = lastRemainder[remainder];
for (i = 0; i < digit; i++){
if (i == repeatDigit)
result[resultIndex++] = '(';
result[resultIndex++] = decimal[i];
}
result[resultIndex++] = ')';
break;
}

lastRemainder[remainder] = digit;
//长除法
numerator = remainder * 10;
decimal[digit] = numerator / denominator + '0';
remainder = numerator % denominator;
digit++;
}

result[resultIndex++] = '\0';
for (i = 0; i < resultIndex; i += 76)
printf("%.76s\n", &result[i]);

#if DEBUG
}
#endif
return 0;
}