challenge_programming的3n+1問題

#include<stdio.h>

int count(int n)

{

//sum爲循環節長度

int sum = 1;

while(n != 1)

{

n = (n%2 == 0) ? n/2 : 3*n+1;

sum++;

}

return sum;

}

int calculate(int i, int j)

{

//n用來遍歷從i到j

int n = 0;

//outcome是最終結果

int outcome = 0;

//temp中間變量

int temp = 0;

for(n = i; n <= j; n++)

{

temp = count(n);

if(outcome < temp)

outcome = temp;

}

return outcome;

}

void main()

{

//定義兩個變量，表示從i到j的全部數

int i = 0, j = 0;

//將數據讀到a和b數組中去

int a[10] = {0}, b[10] = {0};

//n是循環節長度

int n = 0;

//表明是第幾組數據

int x = 0;

//中間變量

int temp = 0;

for(x = 0; x < 4; x++)

scanf("%d %d",&a[x],&b[x]);

x = 0;

while (x < 4)

{

i = a[x];

j = b[x];

temp = calculate(i,j);

printf("%d %d %d\n",i,j,temp);

x++;

}

}