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Classic error. . . Because the fully unimodular matrix is destroyed, linear programming cannot guarantee integer solutions. . .
The answer is not LL = =.
const int N = int(1e4) + 9, M = int(1e3) + 9; struct Simplex { DB a[N][M]; int n, m; void pivot(int in, int out) { REP(i, m+1) if(i!=in) a[out][i] /= -a[out][in]; //reset out constraint a[out][in] = 1/a [out][in]; REP(i, n+1) if (i!=out && sgn(a[i][in])) { //Recalculate other constraints DB t = a[i][in]; a[i][in ] = 0; REP(j, m+1) a[i][j] += t*a[out][j]; } } DB run() { while (true) { int in=0, out=0; DB Min=OO; REP_1(i, m) if(sgn(a[0][i])>0) { in=i; break; } if(!in)return a[0][0]; REP_1(i, n) if(sgn(a[i][in])<0&&a[i][0]/-a[i][in]<Min) { Min=a[i][0]/-a[i][in]; out=i; } if(!out)throw ; //unbounded pivot(in, out); } } int gao() { // zb // c A RD(m, n); REP_1(i, m) RD(a[0][i]); REP_1(i, n) { Rush { int l, r; RD(l, r); FOR_1(j, l, r) a[i][j] -= 1; } RD(a[i][0]); } return run(); } } fst; int main() { #ifndef ONLINE_JUDGE freopen("in.txt", "r", stdin); //freopen("out.txt", "w", stdout); #endif OT(fst.gao()); }
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