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Problem Description
A Fibonacci sequence is calculated by adding the previous two members the sequence, with the first two members being both 1.
F(1) = 1, F(2) = 1, F(3) = 1,F(4) = 1, F(n>4) = F(n - 1) + F(n-2) + F(n-3) + F(n-4) Your task is to take a number as input, and print that Fibonacci number. |
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Input
Each line will contain an integers. Process to end of file.
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Output
For each case, output the result in a line.
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Sample Input
100 |
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Sample Output
4203968145672990846840663646 Note: No generated Fibonacci number in excess of 2005 digits will be in the test data, ie. F(20) = 66526 has 5 digits. |
View Code
1 #include <stdio.h> 2 #include <string.h> 3 int f[10000][505] = {0}; 4 int main() 5 { 6 int n, carry, sum, i, j, length; 7 //f[number][0] is the length of the number 8 f[1][0] = 1; 9 f[1][1] = 1; 10 f[2][0] = 1; 11 f[2][1] = 1; 12 f[3][0] = 1; 13 f[3][1] = 1; 14 f[4][0] = 1; 15 f[4][1] = 1; 16 while (scanf("%d", &n) != EOF) 17 { 18 if (n < 5) 19 { 20 puts("1"); 21 continue; 22 } 23 for (i = 5; i <= n; i++) 24 { 25 f[i][0] = f[i - 1][0]; 26 carry = 0; 27 //splite the number by four 28 for (j = 1; j <= f[i][0]; j++) 29 { 30 sum = f[i -1][j] + f[i - 2][j] + f[i - 3][j] + f[i - 4][j] + carry; 31 f[i][j] = sum % 10000; 32 carry = sum / 10000; 33 } 34 //if the carry is not zero, then the length must plus one 35 if (carry != 0) 36 { 37 f[i][0]++; 38 f[i][j] = carry; 39 } 40 } 41 //formatted printing 42 length = f[n][0]; 43 printf("%d", f[n][length]); 44 for (i = length - 1; i >= 1; i--) 45 printf("%04d",f[n][i]); 46 printf("\n"); 47 } 48 return 0; 49 }
Main points
firstly, you can't use string in C and if the array is big, you must declare in global variable.
secondly, the question is splitting the number by four, or you will accure Runtime Error (ACCESS_VIOLATION). The one diffence with spliting by one is you should use %d firstly, then use %04d.
