int calculate(char* s) {
int size = 10000, top = 0, num = 0;
bool hasNum = false;
int stack[size];
char op;
while (*s != '\0') {
if (!isdigit(*s) && *s != ' ') {
if (hasNum) {
// if we use num != 0 instand of hasNum, when the input is 0, it will be confused
pushNum(stack, &top, num);
num = 0;
hasNum = false;
}
if (*s == ')') {
int start = top-2;
while (stack[start] != '(') start -= 2;
int n = calcu(stack, start+1, top);
top = start;
pushNum(stack, &top, n);
} else {
stack[top++] = *s;
}
} else if (isdigit(*s)) {
num = num * 10 + *s - '0';
hasNum = true;
}
s++;
}
if (hasNum) {
pushNum(stack, &top, num);
}
return calcu(stack, 0, top);
}
void san_fen()
{
double lc,rc,mid1,mid2,res1,res2,ty ;
lc=0 ;
rc=pi/2 ;
do
{
mid1=(lc+rc)/2 ;
mid2=(mid1+rc)/2 ;
res1=calcu(mid1);
res2=calcu(mid2);
if(res1<res2)lc=mid1 ;
else rc=mid2 ;
}
while(rc-lc>eps);
if(res1<res2)res1=res2 ;
if(res1<y)
{
printf("-1\n");
return ;
}
else
{
er_fen(0,rc);
}
}
void enumerate(int energy, int number, int flag, int count)
{
if(energy * flag == 0 )
{
return;
}
if(energy != flag && energy-flag <= flag)
{
array[count++] = flag;
enumerate(energy-flag, number-1, energy-flag, count);
count--;
enumerate(energy, number, flag-1, count);
}
if(energy != flag && energy-flag > flag)
{
array[count++] = flag;
enumerate(energy-flag, number-1, flag, count);
}
if(energy == flag)
{
array[count++] = flag;
calcu(count, array);
count--;
enumerate(energy, number, flag-1, count);
}
return;
}
int main() {
while (scanf("%d",&p)!=EOF) {
int x,y;
if (calcu(p,x,y)!=-1)
}
return 0;
}
ld calcu(ld R, ld X){
if(X >= R + R)
return 4 * (ld)(1.0) / 3 * (2 * acosl((ld)0)) * R * R * R;
else if(X <= R){
return (2 * acosl((ld)0)) * X * X * (R - X / 3);
}
else{
return 4 * (ld)(1.0) / 3 * (2 * acosl((ld)0)) * R * R * R - calcu(R, R + R - X);
}
}
void er_fen(double lc,double rc)
{
double res,mid ;
while(rc-lc>eps)
{
mid=(lc+rc)/2 ;
res=calcu(mid);
if(res>y)rc=mid ;
else lc=mid ;
}
printf("%.6lf\n",mid);
}
ld cal(ld x){
ld res = x * W * L;
for(int i = 0; i < (n); ++i){
ld v = calcu(r[i], x);
ld vball = 4 * (ld)(1.0) / 3 * (2 * acosl((ld)0)) * r[i] * r[i] * r[i];
if(v >= vball * w[i])
res -= vball * w[i];
else
res -= v;
}
return res;
}
