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nyoj1272表达式求值(递归法)

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感冒时写的,简直不忍直视

#include<iostream>
#include<cstring>
using namespace std;
#define LL long long
char s[1010];
LL judp(int,int);
LL judnum(int,int);
LL judc(int,int);
int fin(int st,int ed);
LL all(LL);
LL num(int st,int ed)
{

LL sum=0;

for(int i=st;i<=ed;++i) sum=sum*10+s[i]-‘0‘;

return sum;
}
LL dfs(int st,int ed)
{

int i,j,pp=judp(st,ed),pnum=judnum(st,ed),pc=judc(st,ed);

if(pnum!=-1)        return num(st,ed);

else if(pp!=-1) {LL t1=dfs(st,pp-1),t2=dfs(pp+1,ed);

return t1+t2;}

else if (pc!=-1){

LL t1=dfs(st,pc-1),t2=dfs(pc+1,ed);

return t1*t2;

}

else if(s[st]==‘(‘&&s[ed]==‘)‘) return dfs(st+1,ed-1);

else if(s[st]==‘S‘){

int mid=fin(st,ed);

LL t1=dfs(st+5,mid-1),t2=dfs(mid+1,ed-1);

return max(all(t1),all(t2));
}
}
LL all(LL a)
{

LL s=0;

while(a){

s+=a%10;

a/=10;}

return s;
}
LL judp(int a,int b)
{

int i,c=0;

for(i=a;i<=b;++i){

if(s[i]==‘(‘) ++c;

else if(s[i]==‘)‘) --c;

if(s[i]==‘+‘&&c==0) return i;

}

return -1;
}
LL judnum(int st,int ed)
{

int flag=1,i,sum=0;

for(i=st;i<=ed;++i)

{

if(!isdigit(s[i])) return -1;

else sum+=s[i]-‘0‘;

}

return sum;
}
LL judc(int st,int ed)
{

int i,j,c=0;

for(int i=st;i<=ed;++i){

if(s[i]==‘(‘) ++c;

if(s[i]==‘)‘) --c;

if(c==0&&s[i]==‘*‘) return i;}

return  -1;
}
int fin(int a,int b)
{

int c=0;

for(int i=a;i<=b;++i){

if(s[i]==‘(‘) ++c;

if(s[i]==‘)‘) --c;

if(c==1&&s[i]==‘,‘) return i;

}
}
int main()
{

int t;

cin>>t;

while(t--) cin>>s,cout<<dfs(0,strlen(s)-1)<<endl;

return 0;
}

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nyoj1272表达式求值(递归法)