#include <iostream>
#include <cstdio>
#include <cstring>
using namespace std;
int main() {
int n, q, r[314160], c[314160], max[314160], ans, b, d;
char s[10];
ans=0;
memset(r, 0, sizeof(r));
memset(c, 0, sizeof(c));
memset(max, 0, sizeof(max));
scanf("%d%d", &n, &q);
for(int i=0; i<q; i++) {
scanf("%s%d%d", s, &b, &d);
if(s[0]=='R') c[b-1]+=d;
else r[b-1]+=d;
}
for(int i=0; i<n; i++) for(int j=0; j<n; j++) if(r[i]+c[j]>max[i]) {
max[i]=r[i]+c[j];
if(max[i]>ans) ans=max[i];
}
printf("%d", ans);
return 0;
}
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