(TOJ) 386 西瓜愛算術 [Python : tree]

http://sprout.tw/oj/pro/386/

主要想法就是如果遇到括號，就一直遞迴下去

Python班完了再放到codepad上XDDD

http://sprout.tw/oj/chal/53947/

def get_pivot( s ):    
    cnt = 0
    for i in range( 3 , len( s ) ):
        if s[ i ] == '(':
            cnt += 1
        elif s[ i ] == ')':
            cnt -= 1
        elif cnt == 0 and s[ i ] == ' ':
            return i
    return -123456789;
        

def f(s) :
    #print("in " + s);
    t = get_pivot(s);
    #print("t = "+str(t));
    a=0;
    b=0;
    if (s[t-1] == ')') :
        tmpt=t-1;
        check=1;
        while (s[tmpt]!='(') or check!=0:
            tmpt-=1;
            if (s[tmpt]==')') :
                check+=1;
            elif (s[tmpt]=='(') :
                check-=1
        a = f(s[tmpt:t])
    else :
        tmpt=t-1;
        tmp=[];
        while (s[tmpt]!=' ') :
            tmp.append(s[tmpt]);
            tmpt-=1;
        a=0;
        for i in range(len(tmp)-1,-1,-1) :
            a=a*10 + int(tmp[i]);
            
    if (s[t+1] == '(') :
        tmpt=t+1;
        check=1;
        while (s[tmpt]!=')') or check!=0:
            tmpt+=1;
            if (s[tmpt]==')') :
                check-=1;
            elif (s[tmpt]=='(') :
                check+=1;
        b = f(s[t+1:tmpt+1])
    else :
        tmpt=t+1;
        tmp=[];
        while (s[tmpt]!=')') :
            tmp.append(s[tmpt]);
            tmpt+=1;
        b=0;
        for i in range(0,len(tmp)) :
            b=b*10 + int(tmp[i]);
            
    #print(s + " : a=" + str(a) +" b= "+str(b));
            
    if s[1]=='+' :
        return a+b;
    elif s[1]=='-' :
        return a-b;
    elif s[1]=='*' :
        return a*b;
    elif s[1]=='/' :
        return a//b;
        
    

n=int(input());
for i in range(0,n) :
    s=input()
    tmp=get_pivot(s)
    
    if tmp==-123456789:
        print(s);
    else :
        if (s[0]!='(') :
            s = "(" + s + ")";
        print(f(s));