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实例9 #9

Open overjjjj opened 3 years ago

overjjjj commented 3 years ago

有一分数序列:2/1,3/2,5/3,8/5,13/8,21/13...求出这个数列的前20项之和。

程序分析:请抓住分子与分母的变化规律。

overjjjj commented 3 years ago

include

int main() { int i,t; float sum=0; float a=2,b=1; for(i=1;i<=20;i++) { sum=sum+a/b; t=a; a=a+b; b=t; } printf("%9.6f\n",sum); }