PAT 甲级 1054. The Dominant Color (20)

Behind the scenes in the computer's memory, color is always talked about as a series of 24 bits of information for each pixel. In an image, the color with the largest proportional area is called the dominant color. A strictly dominant color takes more than half of the total area. Now given an image of resolution M by N (for example, 800x600), you are supposed to point out the strictly dominant color.

Input Specification:

Each input file contains one test case. For each case, the first line contains 2 positive numbers: M (<=800) and N (<=600) which are the resolutions of the image. Then N lines follow, each contains M digital colors in the range [0, 2²⁴). It is guaranteed that the strictly dominant color exists for each input image. All the numbers in a line are separated by a space.

Output Specification:

For each test case, simply print the dominant color in a line.

Sample Input:

5 30 0 255 16777215 2424 24 0 0 2424 0 24 24 24

Sample Output:

24

#include <iostream>#include <map>using namespace std;int main(){    int m,n;    cin>>m>>n;    map<int,int> arr;    int half=m*n/2;    for(int i=0;i<n;i++){        for(int j=0;j<m;j++){            int temp;            cin>>temp;            arr[temp]++;            if(arr[temp]>=half){                cout<<temp<<endl;                  return 0;            }        }    }}