[leetcode]-13. Roman to Integer

代码如下：

int romanToInt(char* s) {
    int a=strlen(s);
    int i,j,k;
    int sum=0;
    for(i=0;i<a;i++)
    {
        if(s[i]=='V')
            sum+=5;
        if(s[i]=='L')
            sum+=50;
        if(s[i]=='D')
            sum+=500;
        if(s[i]=='M')
            sum+=1000;
        if(s[i]=='I')
        {
            if(s[i+1]=='V')
            {
                sum+=4;
                i++;
                continue;
            }
            else if(s[i+1]=='X')
            {
                sum+=9;
                i++;
                continue;
            }
            else
                sum+=1;
        }
        if(s[i]=='X')
        {
            if(s[i+1]=='L')
            {
                sum+=40;
                i++;
                continue;
            }
            else if(s[i+1]=='C')
            {
                sum+=90;
                i++;
                continue;
            }
            else
                sum+=10;
        }
        if(s[i]=='C')
        {
            if(s[i+1]=='D')
            {
                sum+=400;
                i++;
                continue;
            }
            else if(s[i+1]=='M')
            {
                sum+=900;
                i++;
                continue;
            }
            else
                sum+=100;
        }
    }
    return sum;
}