复习题上

 

求

100                                            50                                         10

∑ k                   加            ∑ k*k                加          ∑ 1/k 

k=1                                             k=1                                        k=1

 

 

main() {  long sumOne(int,int);  long sumTwo(int,int);  float sumThree(int,int);  double sum;  sum = sumOne(1,100)+sumTwo(1,50)+sumThree(1,10);  printf("%f\n",sum);  scanf("%f",&sum);}long sumOne(int i,int end){ long sum;  if(i<end)  {    sum= i;    sum+= sumOne(++i,end);  }else  {    sum= i;  }  return sum;}long sumTwo(int i,int end){  long sum;  if(i<end)  {    sum = i*i;    sum += sumTwo(++i,end);  }else{    sum=i*i;  }  return sum;}float sumThree(int i,int end){  float sum;  if(i<end){    sum=1.0/i;    sum+=sumThree(++i,end);  }else  {   sum=1.0/i;  }  return sum;}