C++ :

#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
typedef pair<int,int> PII;
int change[4][4];
int get(int x,int y){//二维转一维
    return x * 4 + y;
}
int main(){
    int st = 0;
    for(int i = 0;i < 4;i++){
        string line;
        cin>>line;
        for(int j = 0;j < 4;j++){
            if(line[j] == '+')  st += 1 << get(i,j);//状态压缩
        }
    }
    for(int i = 0;i < 4;i++){
        for(int j = 0;j < 4;j++){
            for(int k = 0;k < 4;k++){
                change[i][j] += 1 << get(i,k);//改变第i行状态
                change[i][j] += 1 << get(k,j);//改变第j列状态
            }
            change[i][j] -= 1 << get(i,j);//恢复重复改变的状态
        }
    }
    vector<PII> res;
    for(int k = 0;k < 1 << 16;k++){//枚举所有可能的解法
        int now = st;
        vector<PII> path;
        for(int i = 0;i < 16;i++){
            if(k >> i & 1){
                int x = i / 4,y = i % 4;
                now ^= change[x][y];
                path.push_back({x,y});
            }
        }
        if(!now && (res.empty()|| res.size() > path.size()))    res = path;
        }
    cout<<res.size()<<endl;
    for(auto x : res)   cout<<x.first + 1<<" "<<x.second + 1<<endl;
    return 0;
}