#include #include int xz,n,k; FILE *fp; char sname[30]; void init1() {printf("please input file name:\n"); gets(sname); fp=fopen(sname,"r"); fscanf(fp,"%d%d",&n,&k); printf("\n N=%d K=%d\n",n,k); printf("please(1/2):\n 1.formula Method\n 2.Math Method \n"); scanf("%d",&xz); } long double n_2_1(int k) {long double k1; /* N=2, method 1*/ k1=k; return k1*(k1+1)*(2*k1+1)/6; } long double n_3_1(int k) {long double k1; /* N=3, method 1*/ k1=k; return k1*(k1+1)*(2*k1+1)*(2*k1*k1+2*k1+1)/30; } long double n_2_2(int k) {long double k1,s; /* N=2, method 2 */ int t; s=0; k1=k; for(t=0; t=3) { c1=0; for(t=2; t