Codeforces 752C Santa Claus and Robot 思维

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题意:给出路线,要求在上面放p个点(p尽量小&&pi,pi+1之间为最短路径)

思路 若s[i]和s[j]为pk和pk+1,因为pk->pk+1是最短路径 所以s[i]->s[j]的路径是递增的,(即路径是:曼哈顿距离) 找到最长递增序列的个数即可

#include <iostream>

using namespace std;

int n, Left, Right, Down, Up, sum = 1;
string s;

int main()
{
cin >> n >> s;
for(int i =  0 ; i < n ; i++){
if(s[i] == 'U' && Down){
sum++;
Down = Right = Left = Up = 0;
}
if(s[i] == 'D' && Up){
sum++;
Down = Right = Left = Up = 0;
}
if(s[i] == 'L' && Right){
sum++;
Down = Right = Left = Up = 0;
}
if(s[i] == 'R' && Left){
sum++;
Down = Right = Left = Up = 0;
}
if(s[i] == 'U')
Up++;
if(s[i] == 'D')
Down++;
if(s[i] == 'R')
Right++;
if(s[i] == 'L')
Left++;
}
cout << sum << endl;
return 0;
}